#include<bits/stdc++.h>

using namespace std;
using ll = long long;

ll gcd(ll a,ll b){
    if(a < b) {
        ll tmp = a;
        a = b;
        b = tmp;
    }
    if(b == 0) return a;
    else return gcd(b,a%b);
}

int main(){
    ll x,a,y,b;
    cin >> x >> a >> y >> b;
    if(gcd(x,y) == 1) cout << "No" << endl;
    else{
        if(x < y) cout << "No" << endl;
        else{
            if(a >= b) cout << "Yes" << endl;
            else cout << "No" << endl;
        }
    }

    return 0;
}