#include <bits/stdc++.h>
using namespace std;
long long gcd(long long a, long long b) {
  if (b > a) {
    return gcd(b, a);
  }
  if (b == 0) {
    return a;
  }
  return gcd(b, a % b);
}
long long expo(long long a, long long b, long long mod) {
  long long res = 1;
  while (b > 0) {
    if (b & 1) res = (res * a) % mod;
    a = (a * a) % mod;
    b = b >> 1;
  }
  return res;
}
vector<int> sieve(int n) {
  int *arr = new int[n + 1]();
  vector<int> vect;
  for (int i = 2; i <= n; i++)
    if (arr[i] == 0) {
      vect.push_back(i);
      for (int j = 2 * i; j <= n; j += i) arr[j] = 1;
    }
  return vect;
}
void extendgcd(long long a, long long b, long long *v) {
  if (b == 0) {
    v[0] = 1;
    v[1] = 0;
    v[2] = a;
    return;
  }
  extendgcd(b, a % b, v);
  long long x = v[1];
  v[1] = v[0] - v[1] * (a / b);
  v[0] = x;
  return;
}
long long mminv(long long a, long long b) {
  long long arr[3];
  extendgcd(a, b, arr);
  return arr[0];
}
long long mminvprime(long long a, long long b) { return expo(a, b - 2, b); }
bool revsort(long long a, long long b) { return a > b; }
void swap(int &x, int &y) {
  int temp = x;
  x = y;
  y = temp;
}
long long combination(long long n, long long r, long long m, long long *fact) {
  long long val1 = fact[n];
  long long val2 = mminvprime(fact[r], m);
  long long val3 = mminvprime(fact[n - r], m);
  return ((val1 * val2) % m * val3) % m;
}
long long helper(int index, int cons, int rem, long long *arr, long long ***dp,
                 int n, int k, int x) {
  if (rem > x) return -1;
  if (cons == k) return -1;
  if (index == n && cons < k && rem == x) return 0;
  if (index == n && (cons == k || rem < x)) return -1;
  if (dp[index][cons][rem] != -2) return dp[index][cons][rem];
  long long ans = -1;
  long long ans1 = helper(index + 1, 0, rem + 1, arr, dp, n, k, x);
  if (ans1 != -1) ans1 += arr[index];
  long long ans2 = helper(index + 1, cons + 1, rem, arr, dp, n, k, x);
  ans = max(ans1, ans2);
  dp[index][cons][rem] = ans;
  return dp[index][cons][rem];
}
int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  cout.tie(NULL);
  int n, k, x;
  cin >> n >> k >> x;
  long long arr[n];
  for (int i = 0; i < n; i++) cin >> arr[i];
  long long ***dp = new long long **[n + 1];
  for (int i = 0; i <= n; i++) {
    dp[i] = new long long *[k + 1];
    for (int j = 0; j <= k; j++) {
      dp[i][j] = new long long[x + 1];
      for (int m = 0; m <= x; m++) dp[i][j][m] = -2;
    }
  }
  cout << helper(0, 0, 0, arr, dp, n, k, x) << endl;
  return 0;
}
