[백준/Java] 25304번 :: 영수증

---

import java.util.Scanner;

public class Main
{
	public static void main(String[] args)
	{
		Scanner sc = new Scanner(System.in);

		int total = sc.nextInt();
		int n = sc.nextInt();
		
		for (int i = 0; i < n; i++)
		{
			int a = sc.nextInt();
			int b = sc.nextInt();
			
			total = total - (a*b);
		}
		if (total == 0)
			System.out.print("Yes");
		else
			System.out.print("No");
	}
}