#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <iomanip>
#include <cmath>
#include <stdio.h>
#include <queue>
#include <deque>
#include <cstdio>
#include <set>
#include <map>
#include <bitset>
#include <stack>
#include <cctype>
using namespace std;
int main() {
	long long n, m;
	cin >> n >> m;
	long long now = 0;
	long long nt = 0;
	long long z = 0;
	for (int i = 0; i < m; i++) {
		long long t, p;
		cin >> t >> p;
		t -= nt;
		long long l = max(z, now - t);
		long long r = min(n - 1, now + t);
		if (l <= p && r >= p) {
			continue;
		}
		else {
			cout << "No" << endl;
			return 0;
		}
		now = p;
		nt = t;
	}
	cout << "Yes" << endl;
	return 0;
}