P6.13 P50095 Next prime number

#include <iostream>
using namespace std;

bool prime(int num){

    if(num==0 or num==1)
        return 0;
    for (int i=2;i*i<=num;++i){
        if (num%i==0)
            return 0;
    }
    return 1;
}

int main() {
    int n;
    while (cin>>n and prime(n)) {
        n++;
        while (not prime(n)) n++;
        cout << n << endl;
    }
}