c++ giving wrong answer in codechef

I am getting wrong answer for the given problem. But it is running properly in cpp.sh http://ift.tt/1ezaDoz

my solution is:-

// Example program


#include <iostream>


using namespace std;

int prime(int a)

{

    //cout<<"****check prime****";

    //if(a==0){return ;}

    int j;

    for(j=2;j<=a/2;j++)

    {if((a%j)==0)

{//cout<<endl<<"***   ****"<<j<<endl;

   return j;}

    }

    //cout<<endl<<"***  -1 ****"<<endl;

    return -1;
}


int main()

{

    int t;

    cin>>t;

    int a[t];

    int n;int x=0;

    for(int i=0;i<t;i++)

    {

        cin>>n;

        x=prime(n);

        if(x==-1){a[i]=-1; }

        else{a[i]=0;}

        }

for(int i=0;i<t;i++)

{


    if(a[i]==-1){cout<<"LUCKY NUMBER"<<endl;}

    else{cout<<"sorry"<<endl;}

}   

return 0;
}