#include<bits/stdc++.h>
using namespace std;
#define int long long
#define ii pair <int, int>
#define app push_back
#define all(a) a.begin(), a.end()
#define bp __builtin_popcountll
#define ll long long
#define mp make_pair
#define f first
#define s second
#define Time (double)clock()/CLOCKS_PER_SEC
#define debug(x) std::cout << #x << ": " << x << '\n';

const int N = 3007, INF = 1e18+7;

int a[N], pref[N];
int dp[N][N];

struct Queue_Max {
//pair (i, x)
deque <ii> a;
void add(ii e) {
    while (a.size() && a.back().s <= e.s)   
        a.pop_back();
    a.push_back(e);
}
void del(ii e) {
    if (a.size() && a.front() == e)
        a.pop_front();
}   
int get() {
    if (a.empty())
        return -INF;
    else
        return a.front().s;
}   
} d[N][2];  

signed main() {
    #ifdef HOME
    freopen("input.txt", "r", stdin);
    #else
    #define endl '\n'
    ios_base::sync_with_stdio(0); cin.tie(0);
    #endif

    int n, m, k;
    cin >> n >> k >> m;
    for (int i = 0; i < n; ++i) {
        cin >> a[i];
        pref[i + 1] = pref[i] + a[i];
    }   

    for (int i = 0; i < N; ++i)
        for (int j = 0; j < N; ++j)
            dp[i][j] = -INF;


    auto add = [&] (int i, int j) {
        if (dp[i][j] == -INF)
            return;
        d[j][0].add(mp(i, dp[i][j] - pref[i]));
        d[j][1].add(mp(i, dp[i][j] + pref[i]));                        
    };  

    auto del = [&] (int i, int j) {
        d[j][0].del(mp(i, dp[i][j] - pref[i]));
        d[j][1].del(mp(i, dp[i][j] + pref[i]));                        
    };  

    dp[0][0] = 0;
    add(0, 0);
    for (int i = 1; i <= n; ++i) {
        for (int j = 1; j <= k; ++j) {

            {
            int mx = d[j - 1][0].get();
            if (mx != -INF) {
                dp[i][j] = max(dp[i][j], mx + pref[i]);
            }   
            }

            {
            int mx = d[j - 1][1].get();
            if (mx != -INF)
                dp[i][j] = max(dp[i][j], mx - pref[i]);
            }

            
            /*
            for (int add = 1; add <= i && add <= m; ++add) {
                if (dp[i - add][j - 1] != -INF) {
                    dp[i][j] = max(dp[i][j], dp[i - add][j - 1] + pref[i] - pref[i - add]);
                    dp[i][j] = max(dp[i][j], dp[i - add][j - 1] + pref[i - add] - pref[i]);                    
                }   
            }
            */  
        }   
        for (int j = 0; j <= k; ++j) {

            add(i, j);
            if (i >= m) {
                del(i - m, j);
            }
        }
    }   

    cout << dp[n][k] << endl;
}