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

int main() {
	int N, M;
	cin >> N >> M;
	vector<int> T(M), P(M);
	for (int i = 0; i < M; i++) cin >> T[i] >> P[i];
	int X = 0, Y = 0;
	for (int i = 0; i < M; i++) {
		int MIN = X - T[i] + Y, MAX = X + T[i] - Y;
		if (P[i] < MIN || MAX < P[i]) {
			cout << "No" << endl;
			return 0;
		}
		X = P[i], Y = T[i];
	}
	cout << "Yes" << endl;
}