兄弟，回文数，我输入12321的时候就是对的，但是输入5位数以下的就是错的，这是为啥

int huiwen(int a)
{
int ge, shi, bai, qian, wan;
int f ;
ge = a % 10;
shi = (a / 10) % 10;
bai =( a / 100 )% 10;
qian = (a / 1000) % 10;
wan = (a / 10000) % 10;
if ((ge == wan )&& (shi == qian))
f = 1;
else
f = 0;
return f;
}

int main()
{
int x;
scanf("%d", &x);
if (huiwen(x) == 1)
printf("yes");
else
printf("no");
return 0;
}