import std.stdio;
import std.string;
import std.conv;
import std.algorithm;
import std.range;
import std.array;

/// isOld ===============
bool isOld(int[] old, int[] target){
  if(old.length == 0) return true;
  if(target[0] <= old[0]) return isOld(old[1..$], target[1..$]);
  return false;
}

/// main =============
void main(){
  auto old = readln.strip.split(".").map!(to!int).array;
  auto target = readln.strip.split(".").map!(to!int).array;
  writeln( isOld(old, target) ? "YES" : "NO" );
}