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

int main() {
	long long n,m,i;
	cin >> n >> m;
	vector<pair<long long,long long>> t(m+1);
	t[0]={0,0};
	for(i=1; i<=m; i++){
		cin >> t[i].first >> t[i].second;
	}
	sort(t.begin(),t.end());
	for(i=1; i<=m; i++){
		if((t[i].first-t[i-1].first)<(abs(t[i].second-t[i-1].second))){
			cout << "No" << endl; return 0;
		}
	}
	cout << "Yes" << endl; return 0;
	return 0;
}