Loop 2

#include <bits/stdc++.h>

using namespace std;
typedef long long ll;

int main()
{
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin);
        freopen("output.txt", "w", stdout);
    #endif

    int n;
    cin >> n;
    bool flag=true;
    for(int i=2;i<n/2;i++)
    {
        if(n%i==0)
        {
            flag = false;
            break;
        }
    }
    if(flag)
        printf("%d is a prime number\n",n);
    else
        printf("%d is not a prime number\n",n);

    return 0;
}