/* package whatever; // don't place package name! */
import java.util.*;
 
class Product{
	private int cost, num;
	static int sum = 0;
 
	Product(int cost, int num){
		this.cost = cost;
		this.num = num;
		productSum();
	}
 
	private void productSum() {
		sum += cost * num;
	}
}
/* Name of the class has to be "Main" only if the class is public. */
class Ideone
{
	public static void main (String[] args) throws java.lang.Exception
	{
		// your code goes here
		Scanner sc = new Scanner(System.in);
		int x = sc.nextInt();
		int n = sc.nextInt();
 
		Product[] p = new Product[n];
 
		for(int i = 0; i < n; i++)
			p[i] = new Product(sc.nextInt(), sc.nextInt());
 
		String result = (x == Product.sum) ? "Yes" : "No";
		System.out.println(result);
		sc.close();
	}
}

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MjYwMDAwCjQKMjAwMDAgNQozMDAwMCAyCjEwMDAwIDYKNTAwMCA4

260000
4
20000 5
30000 2
10000 6
5000 8