PROBLEM : http://www.spoj.com/problems/PRIME1/

MY SOURCE CODE:::::: IN GNU G++11 5.1.0

include <bits/stdc++.h>

using namespace std;

void prime(int low,int high) {

int flag=0,i,temp;
if (low > high) {
    temp = low;
    low = high;
    high = temp;
}
while (low <=high)
{
    flag = 0;
    for(i = 2; i <= low/2; ++i)
    {
        if(low % i == 0)
        {
            flag = 1;
            break;
        }
    }
    if (flag == 0 && low!=1)
       cout<<low<<endl;
    ++low;
}

} int main() { long long int n,a,b; cin>>n; while(n--) { cin>>a>>b;prime(a,b);cout<<endl; } return 0; }

Please can anyone correct my solution or tell me the problem in my code......thanks in advance :)