#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
using namespace std;
int n;//n棵树
int m;//木头所需总长度
int A[1000010];
int l;
int r;
inline int flag(int h)//判断是否已经找出h
{
	int sum=0;
	for(int i=0;i<n;++i)
	{
		if(A[i]>h)
		{
			sum+=A[i]-h;
		}
		if(sum>=m)
		{
			return true;
		}
	}
	return false;
}
int main()
{
	freopen("eko.in","r",stdin);
	freopen("eko.out","w",stdout);
	cin>>n>>m;
	for(int i=0;i<n;++i)
	{
		cin>>A[i];
	}
	sort(A,A+n);
	l=A[0];
	r=A[n-1];
	while(l<=r)
	{
		int mid=(l+r)/2;
		if(flag(mid))
		{
			l=mid+1;
		}
		else
		{
			r=mid-1;
		}
	}
	cout<<r;
	return 0;
}