pta中6-7完全平方数，有点不能理解为什么执行不出结果。求指导

Question

#include <stdio.h>
#include <math.h>
int IsTheNumber ( const int N );
int main()
{
int n1, n2, i, cnt;
scanf("%d %d", &n1, &n2);
cnt = 0;
for ( i=n1; i<=n2; i++ ) {
if ( IsTheNumber(i) )
cnt++;
}
printf("cnt = %d\n", cnt);
return 0;
}
int IsTheNumber ( const int N )
{
int kpf,a,b,c,d;
if(sqrt(N)==(int)sqrt(N));
{
a=N/100;
b=N%10;
c=N/10;
d=c%10;
if(a==b||a==d||b==d)
{
return 1;
}
}
return 0;
}

Answer 1

a=N/100;
b=N%10;
c=N/10;
d=c%10;
这里判断重复数字的方法不对，输入的N并不一定是3位数字，代码修改如下：

#include <stdio.h>
#include <math.h>
int IsTheNumber ( const int N );
int main()
{
    int n1, n2, i, cnt;
    scanf("%d %d", &n1, &n2);
    cnt = 0;
    for ( i=n1; i<=n2; i++ ) {
        if ( IsTheNumber(i) )
            cnt++;
    }
    printf("cnt = %d\n", cnt);
    return 0;
}
int IsTheNumber ( const int N )
{
    int a[10],t,i,j;
    if(sqrt((double)N)==(int)sqrt((double)N));
    {
        i=0;
        t = N;
        while(t)
        {
            a[i] = t%10;
            t/=10;
            //判断有无重复数字
            for(j=0;j<i;j++)
            {
                if(a[j]==a[i])
                    return 1;
            }
            i++;
        }
    }
    return 0;
}