using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main(string[] args)
    {
        var input = Console.ReadLine().Split().Select(int.Parse).ToArray();
        var N = input[0];
        var M = input[1];
        var list = new List<int[]>();

        for (int i = 0; i < M; i++)
        {
            var temp = Console.ReadLine().Split().Select(int.Parse).ToArray();
            list.Add(temp);
        }
        list = list.OrderBy(x => x[0]).ToList();

        var current = 0;
        var ans = "Yes";

        foreach (var item in list)
        {
            if (Math.Abs(item[1] - current) > item[0])
            {
                ans = "No";
                break;
            }
            current = item[1];
        }
        Console.WriteLine(ans);
    }
}