/* -*- coding: utf-8 -*-
 *
 * 2508.cc:  No.2508 Discriminant - yukicoder
 */

#include<cstdio>
#include<cstring>
#include<algorithm>
 
using namespace std;

/* constant */

const int MAX_N = 100000;

/* typedef */

/* global variables */

char a[MAX_N + 4], p[MAX_N + 4], q[MAX_N + 4];

/* subroutines */

/* main */

int main() {
  scanf("%s%s%s", a, p, q);

  if (! strcmp(p, q) || a[0] == '-') puts("No");
  else puts("Yes");
  
  return 0;
}