#coding:utf-8

from heapq import heapify,heappop,heappush

N,M=map(int,raw_input().split())
C=map(int,raw_input().split())
C1=C

heapify(C)

cnt=0
while M:
	s=heappop(C)
	s-=1
	M-=1
	if s!=0:
		heappush(C,s)
	else:
		cnt+=1

print cnt