#include <bits/stdc++.h>
using namespace std;

const int mod = 998244353;
const int Mod = 1000000007;
#define rep(i, n) for (ll i = 0; i < n; i++)
#define all(x) (x).begin(),(x).end()
const long long INF = 1LL << 60;
using ll = long long;
using ld = long double;
#define v2d(type,H,W,name,value) vector<vector<type>> name(H,vector<type>(W,value));

int main()
{
  ll N;
  cin >> N;

  ll a,b,c;
  cin >> a >> b >> c;

  if(a==c){
    cout << "No" << endl;
    return 0;
  }
  if(b==c){
    cout << "Yes" << endl;
    return 0;
  }

  c+=N;

  if(a<b){
    cout << "No" << endl;
    return 0;
  }
  if(b<a){
    cout << "Yes" << endl;
    return 0;
  }

  

}