#include<stdio.h>
int main(void)
{   
int guess=1;
printf("Uh..is your number %d?\n",guess); 

    while(getchar()!='y')
    
    printf("Well,then,is it %d?\n",guess++);

printf("i konw i could do it\n");

return 0;
}

首先打印Uh..is your number 1
然后要求输入，如果等于Y，打印i konw i could do it
如果等于N，打印Well,then,is it %d?
假如如下
Uh..is your number 1?
键入n
Well,then,is it 2?
n
Well,then,is it 3?
y
i konw i could do it
这个是预期结果，可是为什么每次输入N后就连续打印2次
Well,then,is it 2?
Well,then,is it 3?
n
Well,then,is it 4?
Well,then,is it 5?

while(getchar()!='y')
 { printf("Well,then,is it %d?\n",++guess);getchar();}
或者
while(getchar()!='y'&&getchar()!=NULL)
 printf("Well,then,is it %d?\n",++guess);

因为getchar是从流中得到一个字串~~你输入的时候还有个回车~~

是字符

因为getchar()每次只能接受一个字符，你的回车也算一个的，所以返回两个结果
函数可以改为下面的就可以啦#include<stdio.h>
 int main(void)
 {   
 int guess=1;
 printf("Uh..is your number %d?\n",guess);

    while(getchar()!='y')
     
    {
        printf("Well,then,is it %d?\n",guess++);
        if(getchar()=='\n')
            continue;
    }

printf("i konw i could do it\n");
 
return 0;
 }

#include<stdio.h>
int main(void)
{
int guess = 1;
char ture = 'I konw I could do it';
printf("Uh..is your number%d?\n",guess);
if
{
    while(getchar() = "ｎ")
    printf("When,then,is it%d\n ",guess++);
}
else if
{
    scanf = ("y");
    putchar("ture\n");
}
return 0;
}

回车了两下