#include <iostream>
#include <algorithm>
using namespace std;

const int MAX_N = 1000000;
long long tree[MAX_N];

int main() {
    int N;
    long long M;
    cin >> N >> M;
    
    long long max_height = 0;
    for (int i = 0; i < N; i++) {
        cin >> tree[i];
        if (tree[i] > max_height) {
            max_height = tree[i];
        }
    }
    
    long long left = 0;
    long long right = max_height;
    long long result = 0;
    
    while (left <= right) {
        long long mid = (left + right) / 2;
        long long total = 0;
        
        for (int i = 0; i < N; i++) {
            if (tree[i] > mid) {
                total += tree[i] - mid;
            }
        }
        
        if (total >= M) {
            result = mid;
            left = mid + 1;
        } else {
            right = mid - 1;
        }
    }
    
    cout << result << endl;
    
    return 0;
}