import algorithm, strutils, sequtils

let l = stdin.readLine().parseInt()
discard stdin.readLine()
let sortedW = stdin.readLine().split(' ').map(parseInt).sorted(proc (x, y: int): int = x - y)

var sum: int = 0
for idx, w in sortedW:
  sum += w
  if sum >= l:
    echo idx
    break