daily 1

CF 80A

#include<iostream>


#include<algorithm>


using namespace std;


int prime[17]={-1,2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53},n,m;


int main(){


    cin>>n>>m;


    if(*upper_bound(prime,prime+17,m)==n || *upper_bound(prime,prime+17,m)==n) cout<<"YES";


    else cout<<"NO\n";


    return 0;


}