#include<iostream>
#include<cstdio>
using namespace std;
unsigned long long m,l=0,r=0,ans=0,mid=0;
int a[1000010],n;
unsigned long long check(unsigned long long x)
{
	unsigned long long ss=0;
	for(int i=0;i<n;i++)
		if(a[i]>=x)
			ss+=(a[i]-x);
	return ss;
}
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];
		if(a[i]>r)
			r=a[i];
	}
	while(l<=r)
	{
		int mid=(l+r)/2;
		if(check(mid)>=m)
		{
			ans=mid;
			l=mid+1;
		}
		else
			r=mid-1;
	}
	cout<<ans;
	return 0;
}