#include <bits/stdc++.h>

using namespace std;

const int N = 1e6 + 10;



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

    if (y1 == y2) puts("Yes");
    else puts("No");
    
    //system("pause");
    
    return 0;
}