第一章 C++的初步知识
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//1.2 求和 void test1() { int a, b, sum; cin >> a >> b; sum = a + b; cout << "a+b=" << sum << endl; } //1.3 求最大值 int max(int x, int y) { if (x > y) { return x; } return y; } void test2() { int a, b, m; cin >> a >> b; m = max(a, b); cout << "max = " << m << endl; } //1.4 面向对象 class Student { private: int num; int score; public: void setdata() { cin >> num; cin >> score; } void display() { cout << "num = " << num << endl; cout << "score = " << score << endl; } }; Student stud1, stud2; void test3() { stud1.setdata(); stud2.setdata(); stud1.display(); stud2.display(); } |
第二章 数据类型与表达式
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//2.1 字符赋给整型变量 void test2_1() { int i, j; i = 'A'; j = 'B'; cout << i << ' ' << j << '\n'; } //2.2 小写字母变大写 a=97 A=65 void test2_2() { char c1='a', c2='b'; c1 = c1 - 32; c2 = c2 - 32; cout << c1 << ' ' << c2 << '\n'; } //2.4 强制类型转换 void test2_4() { float x=3.6; int i; i = (int)x; cout << "x=" << x << ",i=" << i << endl; } //2.5 将有符号数据传给无符号数据 void test2_5() { unsigned short a; short int b = -1; a = b; cout << "a=" << a << endl; } //2.6 逗号 void test2_6() { int x, a; x = (a = 3, 6 * 3); cout <<"x="<< x << endl; x = a = 3, 6 * a; cout << "x=" << x << endl; cout << (3 * 5, 43 - 6 * 5, 67 / 3) << endl; } |
第三章 程序设计初步
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//3_1 各行小数点对齐 void test3_1() { double a = 123.456, b = 3.14159, c = -3214.67; cout << setiosflags(ios::fixed) << setiosflags(ios::right) << setprecision(2);//设置小数点后2为，右对齐 cout << setw(10) << a << endl; //10个字符 cout << setw(10) << b << endl; cout << setw(10) << c << endl; } //3_2 输出单个字符 putchar void test3_2() { char a, b, c; a = 'B', b = 'O', c = 'Y'; putchar(a);putchar(b);putchar(c);putchar('\n'); putchar(66);putchar(79);putchar(89);putchar(10); } //3_3 输入单个字符 getchar void test3_3() { char c; //c = getchar();putchar(c + 32);putchar(10); putchar(getchar() + 32);putchar(10); } //3_4 scanf printf 函数进行输入输出 void test3_4() { int a;float b;char c; scanf_s("%d %b %c", &a, &c, &b); printf("a=%d,b=%f,c=%c\n", a, b, c); } //3_5 求ax^2+bx+c=0的根 void test3_5() { float a, b, c, x1, x2; cin >> a >> b >> c; if (pow(b, 2) - 4 * a * c >= 0) { x1 = (-b + sqrt(b * b - 4 * a * c)) / (2 * a); x2 = (-b - sqrt(b * b - 4 * a * c)) / (2 * a); cout << "x1=" << x1 << endl; cout << "x2=" << x2 << endl; } else { cout << "没有解" << endl; } } //3_6 求三角形面积 void test3_6() { double a, b, c; cout << "please enter a,b,c:"; cin >> a >> b >> c; if (a + b > c&& b + c > a&& a + c > b) { double s, area; s = (a + b + c) / 2; area = sqrt(s * (s - a) * (s - b) * (s - c)); cout << setiosflags(ios::fixed) << setprecision(4); cout << "area=" << area << endl; } else { cout << "it is not trilateral" << endl; } } //3_7 判断是否为大写，是：转小写 否：不动 void test3_7() { char ch; cin >> ch; ch = (ch >= 'A' && ch < 'Z') ? ch + 32 : ch; cout << ch << endl; } //3_8 判断某年是否为闰年 void test3_8() { int year; bool leap; cout << "please enter year:"; cin >> year; if (year % 4 == 0 && year % 100 != 0 || year % 100 == 0 && year % 400 == 0) { leap = true; } else { leap = false; } switch (leap) { case 1:cout << "it is a leap year" << endl;break; default:cout << "it is not a leap year" << endl; } } //3_9 运输公司路程计费 p:运费/吨 w:重 s:距离 d:折扣 f:总运费 f=p*w*s*(1-d) void test3_9() { int c, s; float p, w, d, f; cout << "please enter p,w,s: "; cin >> p >> w >> s; if (s >= 3000)c = 12; else c = s / 250; switch (c) { case 0:d = 0;break; case 1:d = 2;break; case 2: case 3:d = 5;break; case 4: case 5: case 6: case 7:d = 8;break; case 8: case 9: case 10: case 11:d = 10;break; case 12:d = 15;break; } f = p * w * s * (1 - d / 100.0); cout << "freight=" << f << endl; } //3_10 求1+2+3+...+100; for| do while | while void test3_10() { int s = 0; int i = 0; /* for (int i = 0;i <= 100;i++) { s += i; } while(i<=100){ s+=i; i++; } */ do { s += i; i++; } while (i <= 100); cout << "sum=" << s << endl; } //3_12 求pi的近似值 void test3_12() { int s = 1; double n = 1, t = 1, pi = 0; while (fabs(t) > 1e-7) { pi = pi + t; n = n + 2; s = -s; t = s / n; } pi = pi * 4; cout << setiosflags(ios::fixed) << setprecision(6); cout << "pi=" << pi << endl; } //3_13 求fibonacci数列前40个数 void test3_13() { int f = 1, s = 1; int t = f + s; int i = 1; while (i<=40) { cout << "第" << i << "个数为:"; if (i < 3) { cout << 1 << endl; } if (i >= 3) { t = f + s; f = s; s = t; cout << t << endl; } i++; } } //3_14 找出100-200之间的全部素数 void test3_14() { bool prime; for (int i = 100;i <= 200;i++) { prime = true; for (int j = 2;j <= sqrt(i);j++) { if (i % j == 0) { prime = false; break; } } if (prime) { cout << "prime=" << i << endl; } } } //3_15 译密码 E=A+4 void test3_15() { char c; while ((c = getchar()) != '\n') { if (c >= 'A' && c <= 'Z' || c >= 'a' && c <= 'z') { c = c + 4; if (c <= 'Z' + 4 && c > 'Z' || c > 'z') { c = c - 26; } } cout << c; } } |
第四章 函数与预处理
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//4_1 在主函数中调用其他函数 void printstar() { cout << "******" << endl; } void print_message(void) { cout << "welcome to C++!" << endl; } void test4_1() { printstar(); print_message(); printstar(); } //4_2 调用时数据传递 int max4_2(int x, int y) { return x > y ? x : y; } void test4_2() { int a, b, c; cout << "please enter two integer numbers: "; cin >> a >> b; c = max4_2(a, b); cout << "max=" << c << endl; } //4_3 对被调用的函数作声明 void test4_3() { float add(float x, float y); float a, b, c; cout << "pleas enter a,b "; cin >> a >> b; c = add(a, b); cout << "sum=" << c << endl; } float add(float x, float y) { return x + y; } //4_4 函数指定为内置函数 inline int max4_4(int a, int b, int c); void test4_4() { int i = 10, j = 20, k = 30, m; m = max4_4(i, j, k); cout << "max= " << m << endl; } inline int max4_4(int a, int b, int c) { if (b > a) a = b; if (c > a)a = c; return a; } //4_5 函数的重载，类型不同 求3数max void test4_5() { int max4_5(int a, int b, int c); double max4_5(double a, double b, double c); long max4_5(long a, long b, long c); int i1, i2, i3, i; cin >> i1 >> i2 >> i3; i = max4_5(i1, i2, i3); cout << "i_max= " << i << endl; double d1, d2, d3, d; cin >> d1 >> d2 >> d3; d = max4_5(d1, d2, d3); cout << "d_max= " << d << endl; long l1, l2, l3, l; cin >> l1 >> l2 >> l3; l = max4_5(l1, l2, l3); cout << "l_max= " << l << endl; } int max4_5(int a, int b, int c) { if (b > a) a = b; if (c > a)a = c; return a; } double max4_5(double a, double b, double c) { if (b > a) a = b; if (c > a)a = c; return a; } long max4_5(long a, long b, long c) { if (b > a) a = b; if (c > a)a = c; return a; } //4_6 函数的重载，参数不同 void test4_6() { int max4_6(int a, int b, int c); int max4_6(int a, int b); int a, b, c,m1,m2; cin >> a >> b >> c; m1 = max4_6(a, b, c); m2 = max4_6(a, b); cout << "3_max= " << m1 << endl; cout << "2_max=" << m2 << endl; } int max4_6(int a, int b, int c) { if (b > a) a = b; if (c > a) a = c; return a; } int max4_6(int a, int b) { return a > b ? a : b; } //4_7 函数模版 template<typename T> //模版声明 T max4_7(T a, T b, T c) { if (b > a) a = b; if (c > a)c = a; return a; } void test4_7() { int a, b, c,i; a = 10, b = 20, c = 15; i = max4_7(a, b, c); cout << "i_max= " << i << endl; double A, B, C, d; A = 3.7, B = 5.6, C = 1.2; d = max4_7(A, B, C); cout << "d_max= " << d << endl; } //4_8 有默认参数的函数 求max void test4_8() { int max4_8(int a, int b, int c = 0); int a, b, c; cin >> a >> b >> c; cout << "max(a,b,c)= " << max4_8(a, b, c) << endl; } int max4_8(int a, int b, int c) { if (b > a) a = b; if (c > a) a = c; return a; } //4_9 函数的嵌套调用 用弦截法求方程f(x)=x^3-5x^2+16x-80=0 double f(double); double xpoint(double, double); double root(double, double); void test4_9() { double x1, x2, f1, f2, x; do { cout << "input x1,x2: "; cin >> x1 >> x2; f1 = f(x1); f2 = f(x2); } while (f1 * f2 >= 0); x = root(x1, x2); cout << setiosflags(ios::fixed) << setprecision(7); cout << "A roof of equation is " << x << endl; } double f(double x) { double y; y = x * x * x - 5 * x * x + 16 * x - 80; return y; } double xpoint(double x1, double x2) { double y; y = (x1 * f(x2) - x2 * f(x1)) / (f(x2) - f(x1)); return y; } double root(double x1, double x2) { double x, y, y1; y1 = f(x1); do { x = xpoint(x1, x2); y = f(x); if (y * y1 > 0) { x1 = x; } else { x2 = x; } } while (fabs(y) >= 0.00001); return x; } /* 4_10 递归 有5个人坐在一起，问第5个人多少岁?他说 比第4个人大两岁。问第4个人岁数, 他说比第3个 人大两岁。问第3个人，又说比第2个人大两岁。问 第2个人，说比第1个人大两岁。最后问第1个人， 他说是10岁。请问第5个人多大 ?*/ int age(int n) { int c; if (n == 1) c = 10; else c = age(n - 1) + 2; return c; } void test4_10() { cout << age(5) << endl; } //4_11 递归 求n!; int fac(int n) { int s; if (n == 1) { s = 1; } if (n > 1) { s = fac(n - 1) * n; } return s; } void test4_11() { cout << fac(5) << endl; } //4_12 静态局部变量的值 int f(int a) { int b = 0; static int c = 3; b = b + 1; c = c + 1; return a + b + c; } void test4_12() { int a = 2; for (int i = 0;i < 3;i++) { cout << f(a) << endl; } } //4_13 静态局部变量 输出1~5的阶乘值 void test4_13() { int fac4_13(int a); for (int i = 1;i <= 5;i++) { cout << i << "!=" << fac(i) << endl; } } int fac4_13(int a) { static int f = 1; f = f * a; return f; } //4_14 寄存器register 改写阶乘 int fac4_14(int a) { register int i,f; f = 1; for (i = 1;i <= a;i++) { f *= i; } return f; } //4_15 用extern对外部变量作提前引用声明，扩展程序文件的作用域 void test4_15() { int max4_15(int, int); extern int a, b; //变量声明，不是定义 可以再后面定义变量的值，提前使用 cout << max4_15(a, b) << endl; } int a = 15, b = -7; int max4_15(int x, int y) { return x > y ? x : y; } //4_16 外部函数 求max //file1.cpp void test4_16() { extern int max4_16(int x, int y); int a, b; cin >> a >> b; cout << max4_16(a, b) << endl; } //file2.cpp int max4_16(int x, int y) { return x > y ? x : y; } //4_17 条件编译命令 #define RUN //注释查看不同 void test4_17() { int x = 1, y = 2, z = 3; #ifndef RUN cout << "x=" << x << ",y=" << y << ",z=" << z; #endif // !RUN cout << "x*y*z=" << x * y * z << endl; } |
第五章 数组
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//5_1 数组元素的引用 void test5_1() { int i, a[10]; for (i = 0;i <= 9;i++) { a[i] = i; } for (i = 9;i >= 0;i--) { cout << a[i] << endl; } } //5_2 数组 求fibonacci问题 void test5_2() { int a[20] = { 1,1 }; for (int i = 2;i < 20;i++) { a[i] = a[i - 1] + a[i - 2]; } for (int i = 0;i < 20;i++) { cout << a[i] << setw(8); } } //5_3 数组 冒泡排序 void test5_3() { int a[10] = {6,3,2,8,4,7,6,4,8,9}; int i, j, t; for (i = 0;i < 10;i++) { for (int j = 0;j < 10 - i - 1;j++) { if (a[j] > a[j + 1]) { t = a[j]; a[j] = a[j + 1]; a[j + 1] = t; } } } for (int i = 0;i < 10;i++) { cout << a[i] << " "; } cout << endl; } //5_4 二维数组 行列互换(转置) void test5_4() { int a[2][3] = { {1,2,3},{4,5,6} }; int b[3][2] = {}; for (int i = 0;i < 3;i++) { for (int j = 0;j < 2;j++) { b[i][j] = a[j][i]; } } for (int i = 0;i < 3;i++) { for (int j = 0;j < 2;j++) { cout << b[i][j] << " "; } cout << endl; } } //5_5 3*4矩阵，求max void test5_5() { int a[3][4]= { {5,12,23,56},{19,28,37,46},{-12,-34,6,8} }; int max = a[0][0]; int row=0,col=0; for (int i = 0;i < 3;i++) { for (int j = 0;j < 4;j++) { if (max < a[i][j]) { max = a[i][j]; row = i; col = j; } } } cout << "max=" << max << endl; cout << "row = " << row << " " << "col=" << col << endl; } //5_6 5_5的基础下编写max_value函数 void test5_6() { int max_value(int, int); int a[3][4] = { {5,12,23,56},{19,28,37,46},{-12,-34,6,8} }; int max = a[0][0]; int row = 0, col = 0; for (int i = 0;i < 3;i++) { for (int j = 0;j < 4;j++) { max = max_value(a[i][j], max); if (max == a[i][j]) { row = i; col = j; } } } cout << "max=" << max << endl; cout << "row = " << row << " " << "col=" << col << endl; } int max_value(int x, int y) { return x > y ? x : y; } //5_7 数组 选择排序 void test5_7() { void select_sort(int* array, int n); int i; int a[10] = { 6,3,2,8,4,7,6,4,8,9 }; select_sort(a, 10); for (int i = 0;i < 10;i++) { cout << a[i] << " "; } cout << endl; } void select_sort(int* array, int n) { int i, j, k, t; for (i = 0;i < n - 1;i++) { k = i; for (j = i + 1;j < n;j++) { if (array[j] < array[k]) { k = j; } } t = array[k]; array[k] = array[i]; array[i] = t; } } //5_9 字符数组 输出钻石图形 void test5_9() { char diamond[][5] = { {' ',' ','*'},{' ','*',' ','*'},{'*',' ',' ',' ','*'},{' ','*',' ','*'},{' ',' ','*'} }; for (int i = 0;i < 5;i++) { for (int j = 0;j < 5;j++) { cout << diamond[i][j]; } cout << endl; } } //5_10 字符数组 求3个字符串的最大值 void test5_10() { void max_string(char str[][30], int n); int i; char country_name[3][30]; for (i = 0;i < 3;i++) { cin >> country_name[i]; } max_string(country_name, 3); } void max_string(char str[][30], int n) { int i; char string[30]; strcpy_s(string, str[0]); for (i = 0;i < n;i++) { if (strcmp(str[i], string) > 0) { strcpy_s(string, str[i]); } } cout << "the largest string is:" << string << endl; } //5_11 string 字符串运算，输入3个字符串，将字母由小到大的顺序输出。 void test5_11() { string string1, string2, string3, temp; cout << "please input 3 strings:" << endl; cin >> string1 >> string2 >> string3; if (string2 > string3) { temp = string2; string2 = string3; string3 = temp; } if (string1 < string2) { cout << string1 << " " << string2 << " " << string3 << endl; }else if (string1 <= string3) { cout << string2 << " " << string1 << " " << string3 << endl; } else if (string1 > string3) { cout << string2 << " " << string3 << " " << string1 << endl; } } /* 例5.12 -一个班有n个学生，需要把每个学生的简单 材料(姓名和学号)输入计算机保存。然后可以通过 输入某-学生的姓名查找其有关资料。当输入-一个 姓名后， 程序就查找该班中有无此学生，如果有, 则输出他的姓名和学号，如果查不到，则输出“本 班无此人”。 */ int n; string name[50], num[50]; void test5_12() { void input_data(); void search(string find_name); string find_name; cout << "please input number of this class:"; cin >> n; input_data(); cout << "please input name you want find:"; cin >> find_name; search(find_name); } void input_data() { for (int i = 0;i < n;i++) { cout << "input name and No.of student" << i + 1 << ":"; cin >> name[i] >> num[i]; } } void search(string find_name) { int i; bool flag = false; for (i = 0;i < n;i++) { if (name[i] == find_name) { cout << name[i] << " has been found,his number is" << num[i] << endl; flag = true; break; } } if (flag == false) cout << "can't find this name"; } |
第六章 指针
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//指针数组 数组指针 https://www.jianshu.com/p/c9a46f45610a //6_1 通过指针变量访问整型变量 void test6_1() { int a, b; int* p_1, * p_2; a = 100, b = 10; p_1 = &a;p_2 = &b; cout << a << " " << b << endl; cout << *p_1 << " " << *p_2 << endl; } //6_2 指针变量 输入a和b，2个整数，按大到小的顺序输出a和b void test6_2() { int a, b; cin >> a >> b; int* p_1, * p_2,*p; p_1 = &a;p_2 = &b; cout << *p_1 << " " << *p_2 << endl; if (a < b) { p = p_1; p_1 = p_2; p_2 = p; } cout << *p_1 << " " << *p_2 << endl; } //6_3 参数为指针类型 同例6_2 void test6_3() { void swap(int* p1, int* p2); int* p1, * p2, a, b; cin >> a >> b; p1 = &a; p2 = &b; cout << p1 << endl; if (a < b) swap(p1, p2); cout << "max=" << *p1 << " min=" << *p2 << endl; cout << p1 << endl; } void swap(int *p1,int *p2) { int t; t = *p1; *p1 = *p2; *p2 = t; } //6_4 输入a,b,c 3个整数，按由大到小的顺序输出 void test6_4() { void exchange(int*, int*, int*); int a, b, c, * p1, * p2, * p3; cin >> a >> b >> c; p1 = &a;p2 = &b;p3 = &c; exchange(p1, p2, p3); cout << a << " " << b << " " << c << endl; } void exchange(int* p1, int* p2, int* p3) { if (*p1 < *p2) swap(p1, p2); if (*p1 < *p3) swap(p1, p3); if (*p2 < *p3) swap(p2, p3); } //6_5 指针与数组 输出数组中的全部元素 void test6_5() { int a[10] = {7,8,3,4,2,9,8,2,3,10}; int i; for (i = 0;i < 10;i++) { cout << *(a + i) << " "; } cout << endl; int* p; p = a; for (p;p < a + 10;p++) { cout << *p << " "; } cout << endl; } //6_6 指针 将10个整数按由小到大的顺序排列(选择排序) void test6_6() { void select_sort6_6(int* p, int n); int a[10] = {7,8,3,4,6,2,8,7,4,6}, i; select_sort6_6(a, 10); for (i = 0;i < 10;i++) { cout << a[i] << " "; } cout << endl; } void select_sort6_6(int* p, int n) { int i, j, k, t; for (int i = 0;i < n-1;i++) { k = i; for (int j = i + 1;j < n;j++) { if (*(p + j) < *(p + k)) k = j; } t = *(p + i); *(p + i) = *(p + k); *(p + k) = t; } } //6_7 指针多维数组 输出二维数组各元素的值 void test6_7() { int a[3][4] = { {1,3,5,7},{9,11,13,15},{17,19,21,23} }; int* p; for (p = a[0];p < a[0] + 12;p++) { cout << *p << " "; } cout << endl; cout <<a<<" "<< *a << " "<<a[0]<<endl; } //6_8 指针多维数组 输出二维数组任一行任一列元素的值 void test6_8() { int a[3][4] = { {1,3,5,7},{9,11,13,15},{17,19,21,23} }; int(*p)[4], i, j; p = a; cin >> i >> j; cout << *(*(p + i) + j) << endl; } //6_9 指向数组的指针作函数参数 输出数组 void test6_9() { void output(int(*p)[4]); int a[3][4] = { {1,3,5,7},{9,11,13,15},{17,19,21,23} }; output(a); } void output(int(*p)[4]) { for (int i = 0;i < 3;i++) { for (int j = 0;j < 4;j++) { cout<<*(*(p+i)+j)<<" "; } cout << endl; } } //6_10 字符串与指针 用字符数组存放一个字符串 void test6_10() { char str[] = "i love china"; cout << str << endl; } //6_11 字符串与指针 用字符变量存放一个字符串 void test6_11() { string str = "i love china"; cout << str << endl; } //6_12 字符串与指针 用字符指针指向一个字符串 void test6_12() { const char* str = "i love china"; cout << str << endl; } //6_13 字符串与指针 将字符串str1复制为字符串str2 void test6_13() { char str1[] = "i love china!",str2[20], * p1, * p2; p1 = str1; p2 = str2; while (*p1 != '\0') { *p2 = *p1; p1++; p2++; } *p2 = '\0'; p1 = str1; p2 = str2; cout << "str1=" << p1 << endl; cout << "str2=" << p2 << endl; } //6_14 用函数指针变量调用函数 void test6_14() { int max6_14(int,int); int(*p)(int, int); int a, b, m; cin >> a >> b; p = max6_14; //p指向max6_14函数 m = p(a, b); cout << "max=" << m << endl; } int max6_14(int a,int b) { return a > b ? a : b; } //6_15 指针数组 若干字符串按字母顺序(由小到大)输出 void test6_15() { void sort(const char* name[], int n); void print(const char* name[], int n); const char* name[] = { "basic","fortran","c++","pascal","cobol" }; int n = 5; sort(name, n); print(name, n); } void sort(const char* name[], int n) { const char* temp; int i, j, k; for (i = 0;i < n - 1;i++) { for (j = 0;j < n - 1 - i;j++) { if (strcmp(name[j], name[j + 1]) > 0) { temp = name[j]; name[j] = name[j + 1]; name[j + 1] = temp; } } } } void print(const char* name[], int n) { for (int i = 0;i < n;i++) { cout << *(name+i) << " "<<&name[i]<< endl; } } //6_16 指向指针的指针 void test6_16() { void print(const char* name[], int n); const char* name[] = { "basic","fortran","c++","pascal","cobol" }; const char** p; p = name + 2; cout << *p << endl; cout << **p << endl; } //6_17 引用 引用和变量的关系 void test6_17() { int a = 10; int& b = a; a = a * a; cout << a << setw(6) << b << endl; b = b / 5; cout << b << setw(6) << a << endl; } //6_19 值互换 传递变量的指针 void test6_19() { void swap6_19(int *a,int *b); int a = 3, b = 4; cout << a <<" "<< b << endl; swap6_19(&a, &b); cout << a <<" "<< b << endl; } void swap6_19(int* a, int* b) { int t; t = *a; *a = *b; *b = t; } //6_20 值互换 传送变量的别名 void test6_20() { void swap6_19(int& a, int& b); int a = 3, b = 4; cout << a << " " << b << endl; swap6_19(a, b); cout << a << " " << b << endl; } void swap6_19(int& a, int& b) { int temp; temp = a; a = b; b = temp; } //6_21 对3个变量按由小到大的顺序排序 void test6_21() { void sort6_21(int&, int&, int&); int a, b, c; int a1, b1, c1; cout << "please input 3 integers:"; cin >> a >> b >> c; a1 = a;b1 = b;c1 = c; sort6_21(a1, b1, c1); cout << "sorted order is" << a1 << " " << b1 << " " << c1 << endl; } void sort6_21(int& a, int& b, int& c) { int t; if (a > b) { t = a; a = b; b = t; } if (a > c) { t = a; a = c; c = t; } if (b > c) { t = b; b = c; c = t; } } |
第七章 自定义数据类型
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//7_1 引用结构体变量中的成员 struct Date { int month; int day; int year; }; struct Student { int num; char name[20]; char sex; Date birthday; float score; }student1, student2 = {10002,"Doto",'M',5,23,1982,99}; void test7_1() { student1 = student2; cout << student1.num << endl; cout << student1.name << endl; cout << student1.sex << endl; cout << student1.score << endl; cout << student1.birthday.year << "/" << student1.birthday.month << "/" << student1.birthday.day << endl; } //7_2 结构体数组 /* 对候选人得票的统计程序。设有3个候选人, 最终只能有1人当选为领导。今有10个人参加投 票，从键盘先后输入这10个人所投的候选人的名 字，要求最后输出这3个候选人的得票结果。 可以定义一个候选人结构体数组，包括3个元素, 在每个元素中存放有关的数据。 */ struct Person { char name[20]; int count; }; void test7_2() { Person leader[3] = { {"Doto",0},{"Mui",0},{"Salah",0} }; int n; char name[3][10] = { {"Doto"},{"Mui"},{"Salah"} }; cout << "0:doto 1:Mui 2:Salah" << endl; for (int i = 0;i < 10;i++) { cin >> n; for (int j = 0;j < 3;j++) { if (strcmp(name[n], leader[j].name)==0) { leader[j].count++; } } } for (int i = 0;i < 3;i++) { cout << leader[i].name << " " << leader[i].count << endl; } } //7_3 指向结构体变量的指针 指向结构体变量的指针的应用 struct Stu { int num; string name; char sex; float score; }; void test7_3() { Stu student = {1001,"Doto",'M',99}; Stu* p = &student; cout << (*p).name << " " << (*p).num <<" "<< (*p).score << " " << (*p).sex << endl; cout << p->name << " " << p->num << endl; } //7_4 静态链表 next struct Stu7_4 { long num; float score; Stu7_4* next; }; void test7_4() { Stu7_4 a, b, c, * head, * p; a.num = 31001;a.score = 89.5; b.num = 31003;b.score = 90; c.num = 31007;c.score = 85; head = &a; a.next = &b; b.next = &c; c.next = NULL; p = head; do { cout << p->num << " " << p->score << endl; p = p->next; } while (p != NULL); } //7_5 结构体变量作为函数参数 指向结构体变量的指针作实参 结构体变量的引用作为函数参数 /* 例7.5有-一个结构体变量stu, 内含学生学号、姓名 和3门课的成绩。要求在main函数中为各成员赋 值，在另一函数print中将它们的值输出。 */ struct Stu7_5 { int num; char name[20]; float score[3]; }; void test7_5() { void print(Stu7_5); void print(Stu7_5*); void print2(Stu7_5&); //结构体变量作为函数参数 Stu7_5 stu = { 1001,"Doto",{89,90,91} }; print(stu); //指向结构体变量的指针作实参 Stu7_5* p = &stu; print(p); //结构体变量的引用作为函数参数 print2(stu); } //结构体变量作为函数参数 void print(Stu7_5 stu) { cout << stu.name << " " << stu.num << " " << stu.score[0] << " " << stu.score[1] << " " << stu.score[2] << endl; } //指向结构体变量的指针作实参 void print(Stu7_5 *p) { cout << p->name << " " << p->num << " " << p->score[0] << " " << p->score[1] << " " << p->score[2] << endl; } //结构体变量的引用作为函数参数 void print2(Stu7_5 &stu) { cout << stu.name << " " << stu.num << " " << stu.score[0] << " " << stu.score[1] << " " << stu.score[2] << endl; } //7_6 动态分配和插销内存 struct Stu7_6 { string name; int num; char sex; }; void test7_6() { Stu7_6* p; p = new Stu7_6; p->name = "Doto"; p->num = 1001; p->sex = 'M'; cout << p->name << " " << p->num << " " << p->sex << endl; delete p; } //7_7 共用体 一个表格存入学生和老师的数据 根据job判断是学生还老师第5列学生是class，老师是position struct Person7_7 { int num; char name[10]; char sex; char job; union p { int grade; char position[10]; }category; }person[2]; void test7_7() { int i; for (i = 0;i < 2;i++) { cin >> person[i].num >> person[i].name >> person[i].sex >> person[i].job; if (person[i].job == 's') cin >> person[i].category.grade; else if (person[i].job == 't') cin >> person[i].category.position; } cout << endl << "No. name sex job grade/position" << endl; for (i = 0;i < 2;i++) { if (person[i].job == 's') { cout << person[i].num << person[i].name << person[i].sex << person[i].job << person[i].category.grade; } else { cout << person[i].num << person[i].name << person[i].sex << person[i].job << person[i].category.position; } } } //7_8 枚举类型 /* 口袋中有红、黄、蓝、白、黑5种颜色的球若 千个。每次从口袋中任意取出3个球，问得到3种不 同颜色的球的可能取法，输出每种排列的情况。 */ void test7_8() { enum color{red,yellow,blue,white,black}; color pri; int n = 0; for (int i = red;i <= black;i++) { for (int j = red;j <= black;j++) { if (i != j) { for(int k=red;k<=black;k++) if ((k != i) && (k != j)) { //当3个球均不相同时 n = n + 1; for (int loop = 0;loop < 3;loop++) { //对3个球做处理 switch (loop) { case 0:pri = color(i);break; case 1:pri = color(j);break; case 2:pri = color(k);break; default:break; } switch (pri) { case red:cout << setw(8) << "red";break; case yellow:cout << setw(8) << "yellow";break; case blue:cout << setw(8) << "blue";break; case white:cout << setw(8) << "white";break; case black:cout << setw(8) << "black";break; default:break; } } cout << endl; } } } } cout << "n=" << n << endl; } |
第八章 类和对象
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//8_1 类和对象 举例1 class Time { public: int hour; int minute; int sec; void set_time(); void show_time(); }; void test8_1() { Time t1; cin >> t1.hour; cin >> t1.minute; cin >> t1.sec; cout << t1.hour << ":" << t1.minute << ":" << t1.sec << endl; } //8_2 应用多个对象的成员 void test8_2(){ void set_time(Time&, int hour = 0, int minute = 0, int sec = 0); void show_time(Time); Time t1; Time t2; set_time(t1); set_time(t2,13,20,99); show_time(t1); show_time(t2); } void set_time(Time& t, int hour, int minute, int sec) { t.hour = hour; t.minute = minute; t.sec = sec; } void show_time(Time t) { cout << t.hour << ":" << t.minute << ":" << t.sec << endl; } //8_3 将8_2改用含成员函数的类处理 void test8_3() { Time t; t.set_time(); t.show_time(); } void Time::set_time() { cin >> hour >> minute >> sec; } void Time::show_time() { cout << hour << ":" << minute << ":" << sec << endl; } //8_4 类 找出一个整型数组中的元素的最大值 class Array_max { private: int a[5]; int max; public: void set_value(); void max_value(); void show_value(); }; void Array_max::set_value() { for (int i = 0;i < 5;i++) { cin >> a[i]; } } void Array_max::max_value() { max = a[0]; for (int i = 0;i < 5;i++) { if (max < a[i]) { max = a[i]; } } } void Array_max::show_value() { cout << "max=" << max << endl; } void test8_4() { Array_max arrmax; arrmax.set_value(); arrmax.max_value(); arrmax.show_value(); } |
第九章 关于类和对象的进一步讨论
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//9_1 构造成员函数 定义构造成员函数 class Time9_1 { private: int hour; int minute; int sec; public: Time9_1() { hour = 0; minute = 0; sec = 0; } void set_time(); void show_time(); }; /*也可以 Time9_1::Time9_1() { hour = 0; minute = 0; sec = 0; } */ void Time9_1::set_time() { cin >> hour >> minute >> sec; } void Time9_1::show_time() { cout << hour << ":" << minute << ":" << sec << endl; } void test9_1() { Time9_1 t1; t1.show_time(); t1.set_time(); t1.show_time(); } //9_2 带参数的构造函数 有2个长方柱，有长宽高，求体积 class Box { private: int height; int width; int length; public: Box(); //构造函数的的重载 Box(int, int, int); //Box(int h = 19, int w = 1, int l = 20); int volume(); }; //或者：Box::Box(int h,int w,int l):height(h),width(w),length(l){} Box::Box(int h,int w,int l) { height = h; width = w; length = l; } int Box::volume() { return height * width * length; } void test9_2() { Box b(12, 12, 12); cout << "volume =" << b.volume() << endl; } //9_3 构造函数的重载 /* ... public: Box(); //构造函数的的重载 Box(int, int, int); ... Box::Box(int h,int w,int l) { height = h; width = w; length = l; } */ Box::Box() { width = 10; height = 10; length = 10; } void test9_3() { Box b1; Box b2(12, 12, 12); cout << "volume =" << b1.volume() << endl; cout << "volume =" << b2.volume() << endl; } //9_4 使用默认参数的构造函数 改写9_3 若定义了全部是默认参数的构造函数，不能再定义重载构造函数 void test9_4(){ Box b; cout << "volume =" << b.volume() << endl; } /* class Box { private: int height; int width; int length; public: Box(int h = 19, int w = 1, int l = 20); int volume(); }; Box::Box(int h,int w,int l) { height = h; width = w; length = l; } */ //9_5 析构函数（只有一个） 包含构造函数和析构函数的C++程序 class Stu9_5 { private: int num; string name; char sex; public: Stu9_5(int n, string nam, char s) { num = n; name = nam; sex = s; cout << "Constructor called 1" << endl; } ~Stu9_5() { //定义析构函数 cout << "Destructor called. 2" << endl; } void display() { cout << "num:" << num << endl; cout << "name:" << name << endl; cout << "sex:" << sex << endl; } }; void test9_5() { Stu9_5 s1(1001, "Doto", 'f'); s1.display(); Stu9_5 s2(1002, "Mui", 'f'); s2.display(); } /*结果： Constructor called 1 s1的构造函数 num:1001 name:Doto sex:f Constructor called 1 s2的构造函数 num:1002 name:Mui sex:f Destructor called. 2 s2的析构函数 Destructor called. 2 s1的析构函数 */ //9_6 对象数组（类）的使用方法 class Box9_6 { private: int height; int width; int length; public: Box9_6(int h = 10, int w = 12, int l = 14);//:height(h),width(h),length(l){} int volume(); }; Box9_6::Box9_6(int h, int w, int l) { height = h; width = w; length = l; } int Box9_6::volume() { return height * width * length; } void test9_6() { Box9_6 b[2] = { {1,1,1}, //或Box9_6{1,1,1}, {2,2,2} }; cout << "Vb0= " << b[0].volume() << endl; cout << "Vb1= " << b[1].volume() << endl; } //9_7 对象指针(类)的使用方法 class Time9_7 { public: int hour; int minute; int sec; Time9_7(int h,int m,int s) { hour = h; minute = m; sec = s; } void get_time() { cout << hour << ":" << minute << ":" << sec << endl; } }; void test9_7() { Time9_7 t1(10, 13, 57); int* p1 = &t1.hour; //定义指向整型数据的指针变量p1 cout<<t1.hour<<endl; cout << *p1 << endl; Time9_7* p2 = &t1; //定义指向Time类对象的指针变量p2 t1.get_time(); p2->get_time(); void(Time9_7:: * p3)(); //定义指向Time类公用成员函数的指针变量p3 p3 = &Time9_7::get_time; (t1.*p3)(); } //9_8 对象的常引用 void test9_8() { void fun(const Time9_7&); //加const就不能改变实数的值 Time9_7 t1(10, 13, 56); //fun(t1); cout << t1.hour << endl; } void fun(Time9_7& t) { t.hour = 18; } //9_9 对象的赋值 对象的复制 void test9_9() { Box9_6 b1(11, 11, 11),b2; b2 = b1; cout << "V1 =" << b1.volume(); cout << "V2 =" << b2.volume(); } /* Box::Box(const Box& b){ height =b.height; width=b.width; length=b.length } Box box2(box1) //将box1复制给box2 */ //9_10 引用静态数据成员 class Box9_10 { public: static int height; int width; int length; Box9_10(int, int); int volume(); }; Box9_10::Box9_10(int w, int l) { width = w; length = l; } int Box9_10::volume() { return height * width * length; } int Box9_10::height = 10; void test9_10() { Box9_10 a(11, 11), b(12, 12); cout << a.height << "<-a b->" << b.height << endl; cout << Box9_10::height << endl; //通过类名调用静态成员 cout << a.volume() << " =Va" << endl; cout << b.volume() << " =Vb" << endl; } //9_11 引用非静态成员的具体方法 class Stu9_11 { private: int num; int age; float score; static float sum; static int count; public: Stu9_11(int n, int a, float s) :num(n), age(a), score(s) {}; void total(); static float average(); }; void Stu9_11::total() { sum += score; count++; } float Stu9_11::average() { return (sum / count); } float Stu9_11::sum = 0; int Stu9_11::count = 0; void test9_11() { Stu9_11 s[3] = { {1001,12,70}, {1002,13,88}, {1003,14,90} }; int n; cout << "please input the number of students:"; cin >> n; for (int i = 0;i < n;i++) { s[i].total(); } cout << "the average socre of " << n << " students is" << Stu9_11::average() << endl; //调用静态成员函数 } //9_12 友元函数 将普通函数声明为友元函数 class Time9_12 { private: int hour; int minute; int sec; public: Time9_12(int w,int h,int l) { hour = w; minute = h; sec = l; } friend void display(Time9_12&); //声明友元函数 }; void display(Time9_12& t) { //友元函数，形参t是time类对象的引用 cout << t.hour << ":" << t.minute << ":" << t.sec << endl; } void test9_12() { Time9_12 t(11, 11, 11); display(t); } //9_13 友元成员函数的应用 class Date9_13; //类提前引用声明 class Time9_13 { public: Time9_13(int, int, int); void display(Date9_13 &); //display是成员函数，形参是Date类对象的引用 private: int hour; int minute; int sec; }; class Date9_13 { public: Date9_13(int, int, int); friend void Time9_13::display(Date9_13&); private: int month; int day; int year; }; Time9_13::Time9_13(int h, int m, int s) { hour = h; minute = m; sec = s; } void Time9_13::display(Date9_13& d) { cout << d.year << "/" << d.month << "/" << d.day << endl; cout << hour << ":" << minute << ":" << sec << endl; } Date9_13::Date9_13(int m, int d, int y) { month = m; day = d; year = y; } void test9_13() { Time9_13 t(10, 13, 55); Date9_13 d(12, 25, 2004); t.display(d); } //9_14 类模板 实现整数/浮点数/字符的比较 template <class numtype> class Compare { public: Compare(numtype a, numtype b) { x = a;y = b; } numtype max() { return (x > y) ? x : y; } numtype min() { return (x > y) ? y : x; } private: numtype x, y; }; /*类外定义函数 numtype Compare<numtype>::max(){ return x>y?x:y; } */ void test9_14() { Compare<int> cmp1(3, 7); Compare<float> cmp2(2.3, 2.7); Compare<char> cmp3('A', 'a'); cout << cmp1.max() << endl; cout << cmp2.max() << endl; cout << cmp3.max() << endl; } |
第十章 运算符重载
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//10_1 通过函数来实现复数相加 class Complex { private: double real; double imag; public: Complex() { real = 0; imag = 0; } Complex(double r, double i) { real = r; imag = i; } Complex complex_add(Complex c2); //声明复数相加函数 //Complex operator+(Complex c2); //10_2 声明重载运算符的函数 friend Complex operator+(Complex& c1, Complex& c2);//10_3 定义作为友元函数的重载函数 void display(); friend ostream& operator<<(ostream&, Complex&); //10_7 运算符"<<"重载为友元函数 friend istream& operator>>(istream&, Complex&); //10_8 运算符">>"重载为友元函数 operator double(); //10_9 类型转换函数 }; Complex Complex::complex_add(Complex c2) { Complex c; c.real = real + c2.real; c.imag = imag + c2.imag; return c; } void Complex::display() { cout << "(" << real << "," << imag << "i)" << endl; } void test10_1() { Complex c1(3, 4), c2(3, 3),c3; c3=c1.complex_add(c2); c1.display(); c2.display(); c3.display(); } //10_2 改写10_1 重载运算符“+”,使其能用于2个复数相加 /* Complex Complex::operator+(Complex c2) { Complex c; c.real = real + c2.real; c.imag = imag + c2.imag; return c; } */ void test10_2() { Complex c1(3, 4), c2(3, 3), c3; c3 = c2 + c1; c1.display(); c2.display(); c3.display(); } //10_3 将运算符"+"重载为适用于复数加法，重载函数不作为成员函数，而放在类外，作为Complex类的友元函数。 /* ... friend Complex operator+(Complex &c1,Complex &c2); //10_2 声明重载运算符的函数 ... */ Complex operator+(Complex& c1, Complex& c2) { return Complex(c1.real + c2.real, c1.imag + c2.imag); //不能用this } void test10_3() { Complex c1(3, 4), c2(3, 3), c3; c3 = c2 + c1; c1.display(); c2.display(); c3.display(); } //10_4 重载双目运算符 定义一个字符串类String，用来存放不定长的字符串，重载运算符==,<,>,用于字符串的比较运算 class String { private: const char * p; public: String() { p = NULL; } String(const char* str); friend bool operator>(String& s1, String& s2); //声明运算符函数为友元函数 friend bool operator<(String& s1, String& s2); //声明运算符函数为友元函数 friend bool operator==(String& s1, String& s2); //声明运算符函数为友元函数 void display(); }; String::String(const char* str) { p = str; } bool operator>(String& s1, String& s2) { if (strcmp(s1.p, s2.p) > 0) return true; return false; } bool operator<(String& s1, String& s2) { if (strcmp(s1.p, s2.p) < 0) return true; return false; } bool operator==(String& s1, String& s2) { if (strcmp(s1.p, s2.p) == 0) return true; return false; } void String::display() { cout << p; } void test10_4() { String string1("Hello"), string2("Book"); string1.display(); string2.display(); cout << endl; cout << (string1 > string2) << endl; cout << (string1 < string2) << endl; cout << (string1 == string2) << endl; } //10_5 重载单目运算符 有一个Time类，包含数据成员minute(分)和sec(秒)，模拟秒表60秒进一分钟 class Time { private: int minute; int sec; public: Time() { minute = 0; sec = 0; } Time(int m, int s) :minute(m), sec(s) {} //构造重载函数 Time operator++(); //声明前置自增运算符“++”重载函数 Time operator++(int); //声明后置自增运算符“++”重载函数 void display() { cout << minute << ":" << sec << endl; } }; Time Time::operator++() { //定义前置自增运算符“++”重载函数 if (++sec >= 60) { sec -= 60; minute++; } return *this; } Time Time::operator++(int) { Time temp(*this); sec++; if (sec >= 60) { sec -= 60; ++minute; } return temp; } void test10_5() { Time t(0, 0); for (int i = 0;i < 121;i++) { ++t; } t.display(); //(t++).display(); //(++t).display(); t++; t.display(); ++t; t.display(); } //10_7 重载流插入运算符“<<” 参见10_1声明 /* friend ostream& operator<<(ostream&, Complex&); //运算符"<<"重载为友元函数 */ ostream& operator<<(ostream& output, Complex& c) { //定义运算符"<<"重载函数 if(c.imag>=0) output << "(" << c.real << "+" << c.imag << "i)" << endl; else output << "(" << c.real << "" << c.imag << "i)" << endl; return output; } void test10_7() { Complex c1(2, 4), c2(3, 6), c3; c3 = c1 + c2; cout << c3; } //10_8 重载流插入运算符“>>” 参见10_1声明 /* friend istream& operator<<(istream&, Complex&); //运算符">>"重载为友元函数 */ istream& operator>>(istream& input, Complex& c) { //定义运算符">>"重载函数 cout << "input real part and imaginary part complex number:"; input >> c.real >> c.imag; return input; } void test10_8() { Complex c1; cin >> c1; cout << c1; } //10_9 类型转换函数的简单例子 Complex::operator double() { return real; } void test10_9() { Complex c1(3, 4), c2(3, 3), c3; double d; d = 2.5 + c1; cout << d << endl; } |
第十一章 继承和派生
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//11_1 访问共有基类的成员 class Student { private: int num; string name; char sex; public: void get_value() { cin >> num >> name >> sex; } void display() { cout << "num:" << num << endl; cout << "name" << name << endl; cout << "sex" << sex << endl; } }; class Student1 :public Student { //以public方式声明派生类Student1 private: int age; string addr; public: void display_1() { //cout << "num:" << num << endl;错误 引用基类私有成员 //cout << "name" << name << endl; //cout << "sex" << sex << endl; cout << age << endl; cout << addr << endl; } }; void test11_1() { Student1 stud; stud.display(); //调用基类的公用成员函数 stud.display_1(); //调用派生类的公用成员函数 } //11_2 将11_1中的公用继承方式改为用私有继承方式 class Student2 :private Student { //以私有继承方式声明派生类Student1 private: int age; string addr; public: void display_1() { display(); //正确：调用基类的公用成员函数 cout << age << endl; cout << addr << endl; } }; void test11_2() { Student2 stud; //stud.display(); //错误：私有基类的公用成员函数在派生类中是私有函数 stud.display_1(); //调用派生类的公用成员函数 //stud.age = 18; //错误：外界不能引用派生类的私有成员 } //11_3 在派生类中引用保护成员 class Stu11_3 { protected: int num; string name; char sex; public: void get_value() { cin >> num >> name >> sex; } void display() { cout << "num:" << num << endl; cout << "name" << name << endl; cout << "sex" << sex << endl; } }; class Student3 :protected Stu11_3 { private: int age; string addr; public: void get_value1() { get_value(); cin >> age >> addr; } void display1() { cout << "num:" << num << endl; //num、name、sex是基类中的保护成员 均合法 cout << "name:" << name << endl; cout << "sex:" << sex << endl; cout << "age:"<<age << endl; cout <<"addr:" <<addr << endl; } }; void test11_3() { Student3 s1; s1.get_value1(); s1.display1(); //s1.num = 111; //错误 外界不能访问保护成员 } //11_5 简单的派生类的构造函数 class Stu11_5 { protected: int num; string name; char sex; public: Stu11_5(int n,string nam, char s) { cout << "constructor ! 1" << endl; num = n; name = nam; sex = s; } ~Stu11_5() { cout << "deconstructor ! 1" << endl; } }; class Student5 :public Stu11_5 { private: int age; string addr; public: Student5(int n, string nam, char s, int a, string ad):Stu11_5(n, nam, s) { //派生类构造函数 参数初始化列表调用基类构造函数 cout << "constructor ! 2" << endl; age = a; addr = ad; } void show() { cout << "num:" << num << endl; //num、name、sex是基类中的保护成员 均合法 cout << "name:" << name << endl; cout << "sex:" << sex << endl; cout << "age:" << age << endl; cout << "addr:" << addr << endl; } ~Student5() { //派生类构造函数 cout << "deconstructor ! 2" << endl; int age; string addr; } }; void test11_5() { Student5 s1(1001, "doto", 'f', 20, "haha"); Student5 s2(1002, "doto2", 'f', 21, "haha2"); s1.show(); s2.show(); } //11_6 包含子对象的派生类的构造函数 class Stu11_6 { protected: int num; string name; public: Stu11_6(int n, string nam) { num = n; name = nam; } void display() { cout << "num:" << num << endl << "name:" << name << endl; } }; class Student6 :public Stu11_6 { //声明公用派生类Stu11_6 private: Stu11_6 monitor; //定义子对象 int age; string addr; public: Student6(int n, string nam, int n1, string nam1, int a, string ad) :Stu11_6(n, nam), monitor(n1, nam1) { //派生类构造函数 age = a; addr = ad; } void show() { cout << "This student is:" << endl; display(); cout << "age:" << age << endl; cout << "address" << addr << endl << endl; } void show_monitor() { cout << endl << "Class monitor is:" << endl; monitor.display(); //调用基类成员函数 } }; void test11_6() { Student6 s(1001,"wang-li",1002,"li-sun",19,"beijing"); s.show(); s.show_monitor(); } //11_7 多层派生时的构造函数 class Stu11_7 { protected: int num; string name; public: Stu11_7(int n, string nam) { cout << "constructor ! 1" << endl; num = n; name = nam; } void display() { cout << "num:" << num << endl; cout << "name:" << name << endl; } }; class Student7 :public Stu11_7 { private: int age; public: Student7(int n, string nam, int a) :Stu11_7(n,nam) { cout << "constructor ! 2" << endl; age = a; } void show() { display(); cout << "age:" << age << endl; } }; class Student7_1 :public Student7 { private: int score; public: Student7_1(int n, string nam, int a, int s) :Student7(n, nam, a) { cout << "constructor ! 3" << endl; score = s; } void show_all() { show(); cout << "score:" << score << endl; } }; void test11_7() { Student7_1 s(10010, "li", 17, 89); s.show_all(); } //11_8 多重继承 /* 例11.8声明一个教师(Teacher)类和一一个学生 (Student)类，用多重继承的方式声明一一个研究生 (Graduate)派生类。教师类中包括数据成员 name(姓名)、age(年龄)、 title(职称)。 学生类中包 括数据成员name1(姓名)、age(性 别)、score(成绩)。 在定义派生类对象时给出初始化的数据，然后输出 这些数据。 */ class Tea11_8 { protected: string name; int age; string title; public: Tea11_8(string nam, int a, string t) { name = nam; age = a; title = t; } void display() { cout << "name:" << name << endl; cout << "age" << age << endl; cout << "title:" << title << endl; } }; class Stu11_8 { protected: string name1; char sex; float score; public: Stu11_8(string nam, char s, float sco) { name1 = nam; sex = s; score = sco; } void display() { cout << "name:" << name1 << endl; cout << "sex:" << sex << endl; cout << "score:" << score << endl; } }; class Graduate :public Tea11_8, public Stu11_8 { //声明多重继承的派生类 private: float wage; public: Graduate(string nam, int a, char s, string t, float sco, float w) :Tea11_8(nam, a, t), Stu11_8(nam, s, sco), wage(w) { } void show() { Tea11_8::display(); cout << endl; Stu11_8::display(); cout << "wage:" << wage << endl; } }; void test11_8() { Graduate g1("wang-li", 24, 'f', "assistant", 90, 1234); g1.show(); } //11_9 虚基类的简单应用举例(避免二义性) 在11_8的基础上添加共同基类person class Per11_9 { protected: string name; char sex; int age; public: Per11_9(string nam, char s, int a) { name = nam; sex = s; age = a; } }; class Tea11_9:virtual public Per11_9 { //声明Person为公用继承的虚基类 protected: string title; public: Tea11_9(string nam, char s,int a,string t):Per11_9(nam,s,a) { title = t; } }; class Stu11_9:virtual public Per11_9 { protected: float score; public: Stu11_9(string nam, char s,int a,float sco) :Per11_9(nam,s,a){ ////声明Student为公用继承的虚基类 score = sco; } }; |