function! s:output()
  let this = {'lines': []}

  function! this.append(line) abort
    call add(self.lines, a:line)
  endfunction

  function! this.build() abort
    return join(self.lines, "\n")
  endfunction

  return this
endfunction

function! s:main(input) abort
  let o = s:output()

  let l = str2nr(a:input[0])
  let w_list = map(split(a:input[2], ' '), 'str2nr(v:val)')
  let c = 0
  for w in sort(w_list, 'n')
    let l -= w
    if l < 0
      break
    endif
    let c += 1
  endfor

  call o.append(c)
  return o.build()
endfunction

let s:input = getline(1, '$')
enew
put =s:main(s:input)
2,$print