C语言程序设计苏小红课后习题答案7.14.4

C语言程序设计苏小红课后习题答案7.14.4

//生成随机符号
char Charop()
{int op;op = rand() % 4 + 1;switch (op){case 1:return '+';case 2:return '-';case 3:return '*';case 4:return '/';}return 0;
}
//相关计算
int Calculate(int x, char op, int y)
{int a, b, c, d;a = x + y;b = x - y;c = x * y;d = x / y;switch (op){case '+': return a;case '-': return b;case '*': return c;case '/': return d;default:return 0;}
}
//输出运算
int fun()
{int answer, counter = 0, grade = 0;int x, y, m, n;char op;for (int i = 1;i <= 10;i++){op = Charop();srand(time(NULL));x = rand() % 10 + 1;y = rand() % 10 + 1;printf("%d%c%d=", x, op, y);scanf("%d", &answer);if (answer == Calculate(x, op, y)){printf("Right!n");grade++;}elseprintf("Wrong!n");counter++;}printf("grade=%dn", grade);printf("Scoring rate=%d%%", grade * 10);
}
//主函数
int main()
{fun();return 0;
}