#include <bits/stdc++.h>
using namespace std;
int main(){
  int N;
  cin>>N;
  int a,b,c;
  cin>>a>>b>>c;
  if((a<b&&a<c)||(b<a&&c<a)){
    cout<<"Yes"<<endl;
  }else{
    cout<<"No"<<endl;
  }
}