#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
typedef long long ll;
typedef modint998244353 mint;

int main(){
    string a,p,q;
    cin >> a >> p >> q;
    if(p == q){
        cout << "No" << endl;
    }else{
        cout << "Yes" << endl;
    }
}