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

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);

    int x1,y1,x2,y2,x3; cin >> x1 >> y1 >> x2 >> y2 >> x3;
    if(y1 == y2) cout << "Yes" << endl;
    else cout << "No" << endl;
}