<?php
$box = trim(fgets(STDIN));
$num = trim(fgets(STDIN));
$blocks = explode(" ", (trim(fgets(STDIN))));

sort($blocks);
$ans;$totalBlockSize = 0;
if ( $box == array_sum($blocks)) {
    $ans = count($blocks);
} else {
    for ($i=0; $box > $totalBlockSize; $i++) {
        $totalBlockSize += $blocks[$i];
    }
    $ans = $i - 1;
}
echo $ans."\n";