#include <bits/stdc++.h>
using namespace std;
long long int n, m, k;
const int N = 5005;
long long int dp[N][N];
long long int a[N];
long long int george(long long int i, long long int count_k) {
  if (i > n - m || count_k == k) return 0;
  if (dp[i][count_k] != -1) return dp[i][count_k];
  long long int op1 = 0, op2 = 0;
  for (long long int k = i; k < i + m; k++) {
    op1 += a[k];
  }
  op1 += george(i + m, count_k + 1);
  op2 = george(i + 1, count_k);
  dp[i][count_k] = max(op1, op2);
  return max(op2, op1);
}
int main() {
  memset(dp, -1, sizeof dp);
  cin >> n >> m >> k;
  for (int i = 0; i < n; i++) cin >> a[i];
  cout << george(0, 0);
}
