#include<iostream>

#include<algorithm>

#include<cstdio>

#include<queue>

using namespace std;

priority_queue <int,vector<int>,less<int> > q;

//bool operator  < (int x,int y){

//    return x>y;

//};

int n,k;

int x;

int main(){

    scanf("%d%d",&n,&k);

    for(int i=;i<=n;++i){

        cin>>x;

        q.push(x);

    }

    while(){

        int x=q.top();

        q.pop();

        int y=q.top();

        q.pop();

        q.push((x+y)/k);

        if(q.size()==){

            cout<<q.top();

            return ;

        }

    }

    return ;

}