#include <bits/stdc++.h> 

using namespace std;
using ll=long long;
using ull=unsigned long long;
using pii=pair<int,int>;

#define INF LONG_MAX
#define MOD1 1000000007
#define MOD2 998244353
#define MOD MOD1
#define rng(a) a.begin(),a.end()
#define rrng(a) a.end(),a.begin()
#define endl "\n"
#define int ll

signed main(){
    ios::sync_with_stdio(false);
    cin.tie(0);

    int N,M;
    cin>>N>>M;
    vector<int>A(N);
    for(int i=0;i<N;i++)cin>>A[i];
    int l=0;
    int r=10000000000;
    int m;
    while(r-l>1){
        m=(r+l)/2;
        bool ok=true;
        int d=0;
        for(int i=0;i<N;i++){
            if(A[i]<M*m){
                if(A[i]+d>=M*m){
                    d-=M*m-A[i];
                }
                else{
                    ok=false;
                    break;
                }
            }
            else{
                d+=A[i]-M*m;
            }
        }
        if(ok)l=m;
        else r=m;
    }
    cout<<l<<endl;
    return 0;
}