<?php
$box_length = trim(fgets(STDIN));
$block_num = trim(fgets(STDIN));
$block = trim(fgets(STDIN));

$block_arr = explode(" ", $block);
$block_arr_sort = sort($block_arr);

$block_length = $block_arr[0];

if ($block_arr[0] >= $box_length)
{
	echo 1;
}
else
{
	for ($i = 1; $i < $block_num; $i++)
	{
		$block_length += $block_arr[$i];
		if ($block_length >= $box_length)
		{
			echo $i;
			break;
		}
	}
}