#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cstdlib>
#define ll long long
using namespace std;
ll a[1000001];
ll maxn=-1;
ll n,m;
void erfen(ll s,ll e)
{
	ll mid=(s+e)/2;
	long long sum=0;
	for(int i=1;i<=n;i++)
	{
		if(a[i]>mid)
			sum+=(a[i]-mid);
	}
	if(sum<m)
		erfen(s,mid);
	if(sum>m)
	{
		erfen(mid+1,e);
	}
	if(sum==m)
	{
		printf("%lld",mid);
		exit(0);
	}
}
int main()
{
	freopen("eko.in","r",stdin);
	freopen("eko.out","w",stdout);
	scanf("%lld %lld",&n,&m);
	for(int i=1;i<=n;i++)
	{
		scanf("%lld",&a[i]);
		if(a[i]>maxn)
			maxn=a[i];
	}
	erfen(0,maxn);
	return 0;
}