import java.util.Scanner;

public class HelloWorld {

	    public static void main(String[] args) throws Exception {

	    	Scanner sc = new Scanner(System.in);
	    	String[] str = sc.nextLine().split(" ");
	    	int n = 0;
	    	int m = Integer.parseInt(str[1]);
	    	boolean flag = true;

	    	for (int i = 0; i < m; i ++) {
	    		str = sc.nextLine().split(" ");
	    		if (Integer.parseInt(str[0]) >= n + Integer.parseInt(str[1])) {
	    			n = Integer.parseInt(str[1]);
	    		}else {
	    			flag = false;
	    		}
	    	}

	    	System.out.println(flag ? "Yes" : "No");

	    	}

}