#include<iostream>
#include<algorithm>
using namespace std;
int m/*树木量*/,n/*最少需要*/,tree[1000005];
long long h,ans = 0;
int main(){
	cin>>m>>n;
	int right = 1000000000;
	int left = 0;
	for(int i = 1;i <= m;i++){
		cin>>tree[i];
	}
	sort(tree + 1,tree + m + 1);
	while(left < right){
		ans = 0;
		h = (left+ right) / 2;
		for(int i = 1;i <= m;i++){	
			if(tree[i] > h){	
				ans += tree[i] - h;	
			}
		}
		if(ans < n){
			right = h;
		}
		if(ans > n){
			left = h + 1;
		}
		if(ans == n){
			cout<<h<<endl;
			return 0;
		}
	}
	cout<<left - 1<<endl;
	return 0;
}