#include <bits/stdc++.h>
using namespace std;

int main() {
    int n,k,x;
    cin >> n >> k >> x;
    vector<long long> a;
    vector<long long> b;

    for(int i = 0; i < n; i++){
        long long z;
        cin >> z;
        a.push_back(z);
    }

    for(int i = 0; i < n; i++){
        int m = min(k, i+1);
        sort(a.rend()-i-1, a.rend());
        
        long long sum = 0;
        for(int j = 0; j < m; j++){
            sum += a.at(j);
        }

        long long f = sum - x*(i+1);
        b.push_back(f);
    }

    cout << *max_element(b.begin(), b.end()) << endl;


    return 0;
}