#! ruby
# yukicoder My Practice
# author: Leonardone @ NEETSDKASU

(N, M), c = $<.map{|x| x.split.map(&:to_i)}

M.times do
	c.sort_by!{|x| x == 0 ? 10**5 : x}
	c[0] -= 1
end

puts c.count(0)