Lux Hotel

/*
    Task    : _example
    Author  : Phumipat C. [MAGCARI]
    Language: C++
    Created : 06 February 2023 [20:35]
*/
#include<bits/stdc++.h>
using namespace std;
int qs[100010],dp[100010][2];
int findAns(int n,int k,int p){
    if(n == 0)          return 0;
    if(k == 0)          return 0;
    if(dp[n][k] != 0)   return dp[n][k];
    return dp[n][k] = max(findAns(n-1,k,p),qs[n]-qs[max(0,n-p)] + findAns(max(0,n-p),k-1,p));
}
int main(){
    cin.tie(0)->sync_with_stdio(0);
    cin.exceptions(cin.failbit);
    // a[i] + a[i-1] + a[i-2] + ... + a[i-p+1] + เหลือ i-p ห้องกับ j-1 ครอบครัว
    int n,k,p;
    cin >> n >> k >> p;
    for(int i=1;i<=n;i++)
        cin >> qs[i],qs[i]+=qs[i-1];
    // cout << findAns(n,k,p) << '\n';
    int ans = 0;
    for(int j=1;j<=k;j++){
        for(int i=1;i<=n;i++){
            dp[i][j%2] = max(dp[i-1][j%2],qs[i]-qs[max(0,i-p)] + dp[max(0,i-p)][(j-1)%2]);
            ans = max(ans,dp[i][j%2]);
        }
    }
    cout << ans << '\n';
    return 0;
}