#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template <class T> using vec = vector<T>;
template <class T> using vvec = vector<vec<T>>;

int main(){
    cin.tie(0);
    ios::sync_with_stdio(false);
    vec<int> A(4);
    cin >> A[0] >> A[1] >> A[2] >> A[3];
    cout << ((A[0]<A[1] && A[2]>A[3])? "YES\n":"NO\n");
}