#include <bits/stdc++.h>

using namespace std;

long long x, a, b, y;

long long expo;

long long logaritmo(long long k, long long p){
    int con = 0;
    while(k > p){
        if(k % p != 0)return -1;
        k/= p;
        con++;
    }

    return con;
}

long long logs(long long k, long long p){
    int con = 0;
    while(k >p){
        if(k % p != 0)return -1;
        k /= p;
        con++;
    }

    return con;
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    cin >> x >> a >> y >> b;


    if(x == y && a >= b){
        cout << "Yes";
        return 0;
    }

    if(y == 1){
        cout << "Yes" << '\n';
        return 0;
    }

    if(x == 1){
        cout<< "No" << '\n';
        return 0;
    }

    if(x % y == 0){
        expo = logaritmo(x,y);

        if(expo == -1){
            cout << "No";
            return 0;
        }

        if(a >= b/expo)cout << "Yes";
        else cout << "No";
        return 0;
    }


    if(y % x == 0){
        expo = logs(y,x);

        if(expo == -1){
            cout << "No";
            return 0;
        }

        if(a/expo >= b){
            cout << "Yes";
        }else{
            cout << "No";
        }

    }else{
        cout << "No";
    }






return 0;
}