c 语言的问题求大神的指导！

Question

#include"stdio.h"
#include"stdlib.h"
void main()
{
int guess=0,problem,ch;
ch=getchar();
do
{scanf("%d",&guess);
problem=(int)(rand()%100)+1;
for(;guess!=problem;)
{if(guess>problem)
printf("too high!");
if(guess<problem)
printf("too low!");
scanf("%d",&guess);
}
printf("%d",problem);
ch=getchar();
}while(ch!='n');
}为什么猜完一次数字后，我按任意键程序都会进入死循环！！

Answer 1

你的代码问题在于scanf没有判断输入的是否是数字，如果不是数字，就会进入死循环。加一个判断就好了。
不过你也可以使用fgets之类的替代scanf，方便指定输入数据类型。

#include <stdio.h>
#include <stdlib.h>
void main()
{
    int guess = 0, problem;
    char ch = getchar();
    int isNumber;
    do
    {
        isNumber = scanf("%d", &guess);
        if(isNumber == 0)
        {
            printf("please input a number!");
            ch = getchar();
            continue;
        }
        problem = (int)(rand() % 100) + 1;
        for(; guess != problem;)
        {
            if(guess > problem)
                printf("too high!");
            if(guess < problem)
                printf("too low!");
            scanf("%d", &guess);
        }
        printf("%d", problem);
        ch = getchar();
    }while(ch != 'n');
}