#include <bits/stdc++.h>
using namespace std;
int main(){
    long long N, M;
    cin >> N >> M;
    vector<long long> A(N);
    for(int i = 0; i < N; i++) cin >> A[i];
    long long ub = 1000000000000000000, lb = 0;
    while(ub - lb > 1){
        long long mid = (ub + lb) / 2;
        long long temp = 0;
        for(int i = N - 1; i >= 0; i--){
            if(A[i] >= mid) temp = min(0LL, temp + A[i] - mid);
            else temp += A[i] - mid;
        }
        if(temp >= 0) lb = mid;
        else ub = mid;
    }
    cout << lb / M << endl;
}