我不明白这个。好吧，这是代码，首先。
#include <stdio.h>
void load_menu(void);
void sum(void);
void product(void);
void difference(void);
void rest(void);
int main(int argc, char** argv)
{
load_menu();
return 0;
}
void load_menu(void)
{
int choice;
do
{
printf("Menu\n\n");
printf("1. Sum\n");
printf("2. Product\n");
printf("3. Difference\n");
printf("4. Rest\n");
printf("5. Exit(Bad choice)\n");
scanf_s("%d", &choice);
switch (choice)
{
case 1: sum();
break;
case 2: product();
break;
case 3: difference();
break;
case 4: rest();
break;
case 5: printf("Quitting program!\n");
system("PAUSE");
exit(0);
break;
default: printf("Invalid choice!\n");
break;
}
} while (choice != 3);
}
void sum(void)
{
int num1, num2;
int ch;
printf("Enter number 1: ");
scanf_s("%d", &num1);
printf("Enter number 2: ");
scanf_s("%d", &num2);
printf("\nThe sum of the numbers was: %d", num1 + num2);
while ((ch = getchar()) != '\n' && ch != EOF);
printf("\n\nPress ENTER to continue.");
while ((ch = getchar()) != '\n' && ch != EOF)
;
system("cls");
return;
}
void product(void)
{
int num1, num2;
int ch;
printf("Enter a number 1: ");
scanf_s("%d", &num1);
printf("Enter number 2: ");
scanf_s("%d", &num2);
printf("\nThe product of the numbers was: %d", num1 * num2);
while ((ch = getchar()) != '\n' && ch != EOF);
printf("\n\nPress ENTER to continue.");
while ((ch = getchar()) != '\n' && ch != EOF)
;
system("cls");
return;
}
void difference(void)
{
int num1, num2;
int ch;
printf("Enter a number 1: ");
scanf_s("%d", &num1);
printf("Enter a number 2: ");
scanf_s("%d", &num2);
printf("\nThe difference of the numbers was: %d", num1 - num2);
while ((ch = getchar()) != '\n' && ch != EOF);
printf("\n\nPress ENTER to continue.");
while ((ch = getchar()) != '\n' && ch != EOF)
;
system("cls");
return;
}
void rest(void)
{
int ch;
printf("Sleepy sleepy... zZZzZzZz\n");
printf("You now feel awake again!\n");
while ((ch = getchar()) != '\n' && ch != EOF);
printf("\n\nPress ENTER to continue.");
while ((ch = getchar()) != '\n' && ch != EOF)
;
system("cls");
return;
}
但问题是，在“差异部分”中，当它完成计算后，如果我按 Enter，它就会退出。它应该清除屏幕并重复菜单，但它只是退出？？？其他部分工作正常，但差异部分到底有什么问题？你能找到任何错误或建议吗？我认为这与返回部分有关。我尝试了系统暂停，但它什么也没做，只是暂停，我必须退出。
那么你认为这是什么问题？提前致谢。