#include<iostream>

using namespace std;

int main(void)
{
  char s,t; cin>>s>>t;
  
  if(s=='Y'){cout<<(char)(t-32)<<endl;}
  else{cout<<t<<endl;}
  
  return 0;
}
#include<bits/stdc++.h>
#define FULL(x,y) memset(x,y,sizeof(x))
#define ll long long
#define pb push_back
using namespace std;

int x,y;

int main() {
	cin>>x>>y;
	if (abs(x-y)<3) printf("Yes");
	else printf("No");
	return 0;
}