import java.util.Arrays;
import java.util.Scanner;

public class Yuki1 {
	
	public static void main(String argas[]) {
	
		Scanner scan = new Scanner(System.in);
		// 箱の幅
		int box = scan.nextInt();
		//int box = 16;
		// ブロックの数
		int blockCount = scan.nextInt();
		//int blockCount = 3;
		int num = scan.nextInt();
		int blockWidth[] = new int [num];
		//int blockWidth[] = {10,5,7};
		/*
		for (int i = 0; i <= num; i++) {
			blockWidth[i] = scan.nextInt();
		}*/
		
		Arrays.sort(blockWidth);
		/*
		for(int i = 0; i< 3; i++){
			System.out.println(blockWidth[i]);
		}
		*/
		
		int boxWidthAll = 0;
		int boxWidthAllCount = 0;
		
		while(box>boxWidthAll){
			
			boxWidthAll +=blockWidth[boxWidthAllCount];

			if(box>boxWidthAll) {
				boxWidthAllCount++;
			}
		}
		
		System.out.println(boxWidthAllCount);
	}	
}