#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef pair<int,int> P;
#define REP(i,n) for(int i=0;i<int(n);i++)



int main(void){
	cin.tie(nullptr);  ios_base::sync_with_stdio(false);
	int i,j;

	int X1,Y1,X2,Y2,X3;
	cin >> X1 >> Y1 >> X2 >> Y2 >> X3;


	if(Y1==Y2) cout << "Yes" << endl;
	else cout << "No" << endl;



	return 0;
}