#include<bits/stdc++.h>
using namespace std;
int main(){ 
  int n; cin >> n; int a,b; 
  for(int i = 0; i < n; i++){ 
    int c; cin >> c; if( i == 0){ a = c;} else if( i == n-1){ b = c;}
  }
  
  if( a < b){ cout << "Yes" << endl;} else{ cout << "No" << endl;}
  
  return 0;
}