#include<iostream>
#include<cstdio>
#include<cstring>
#include<cmath>
#include<algorithm>
#include<queue>
using namespace std;

const int N=5e3+5;

int n,m,k;
long long p[N];
long long sum[N];
long long dp[N][N];

int main()
{
    scanf("%d%d%d",&n,&m,&k);
    
 
for(int i=1;i<=n;++i)
    {
        scanf("%lld",p+i);
        sum[i]=sum[i-1]+p[i];
    }
    for(int i=m;i<=n;++i)
    {
        for(int j=1;j<=k;++j)
        {
            dp[i][j]=max(dp[i-1][j],dp[i-m][j-1]+sum[i]-sum[i-m]);
        }
    }
    int ans=-1;
    printf("%lld",dp[n][k]);
    
 
return 0;
}

CF467C George and Job