#include <bits/stdc++.h>
using namespace std;


int main(){
    int x1, y1, x2, y2, x3;  cin >> x1 >> y1 >> x2 >> y2 >> x3;

    if(y1 == y2){
        cout << "Yes" << endl;
    }
    else{
        cout << "No" << endl;
    }

    return 0;
}