#include <bits/stdc++.h>
#include<iostream>
#include<map>
#include<vector>
#include <algorithm>
#include<math.h>
#include <iomanip>
#include<set>
#include <numeric>
#include<string>
using ll = long long;
using namespace std;

int main()
{
    ll n, a, b, c;
    cin >> n >> a >> b >> c;
    cout << (((a > b && a > c) || (a < b && a < c)) ? "Yes" : "No") << endl;
}