# Here your code !

length = gets.to_i #16
num = gets.to_i #3
s = gets.chomp.split(" ").map(&:to_i).sort #[5, 7, 10]

sum = 0
count = 0
i = 0

if s.inject == length
    puts num
else
    while sum < length
      sum = sum + s[i]
      i = i + 1
    end
    puts i - 1
end