<?php
    $x = [];
    while ($line = fgets(STDIN)) {
        $x[] = explode(" ", trim($line)); //各行の値を変数xに代入、保管
    }
    
    $teiin = $x[0][1];
    $tensuu = $x[1];
    rsort($tensuu);
    
    $data = [];
    foreach($tensuu as $v) {
        if (isset($data[$v])) {
            $data[$v]++;
        } else {
            $data[$v] = 1;
        }
        
    }
    
    $tmp = $teiin;
    $res = 0;
    foreach($data as $v) {
        if ($tmp >= $v) {
            $res += $v;
        }
        $tmp = $tmp - $v;
    }
    
    echo $res;