Could not get which testcase is not satisfied here

#1

#include<bits/stdc++.h>
using namespace std;
#define num 10000001
int main()
{
long long int arr[num]={0};
arr[0]=arr[1]=1;
for(long long int i=2;i<num;i++)
{
if(arr[i]==0)
{
for(long long int j=i*i;j<num;j+=2)
{
arr[j]=1;
}
}
}

int n;
cin>>n;
long long int a;
for(int i=0;i<n;i++)
{
    cin>>a;
	float b= sqrt(a);
	if((ceil(b)==floor(b))&& (arr[int(ceil(b))]==0)) 
	{
        cout<<"YES"<<endl;
	}
	else
	{
		cout<<"NO"<<endl;
	}
}
return 0;

}

#2

@goyal431 in inner for loop of your sieve it should be j+=i you have written j+=2,
and 0 and 1 are not prime.

#3

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