#include <bits/stdc++.h>
using namespace std;
using ll = long long;
using ld = long double;
using VI = vector<int>;
using VL = vector<ll>;
using VS = vector<string>;
template<class T> using PQ = priority_queue<T, vector<T>, greater<T>>;
#define FOR(i,a,n) for(int i=(a);i<(n);++i)
#define eFOR(i,a,n) for(int i=(a);i<=(n);++i)
#define rFOR(i,a,n) for(int i=(n)-1;i>=(a);--i)
#define erFOR(i,a,n) for(int i=(n);i>=(a);--i)
#define each(i, a) for(auto &i : a)
#define SORT(a) sort(a.begin(),a.end())
#define rSORT(a) sort(a.rbegin(),a.rend())
#define fSORT(a,f) sort(a.begin(),a.end(),f)
#define all(a) a.begin(),a.end()
#define out(y,x) ((y)<0||h<=(y)||(x)<0||w<=(x))
#define tp(a,i) get<i>(a)
#define line cout << "-----------------------------\n" 
#define ENDL(i,n) ((i) == (n) - 1 ? "\n" : " ")
#define stop system("pause")
constexpr ll INF = 1000000000;
constexpr ll LLINF = 1LL << 60;
constexpr ll mod = 1000000007;
constexpr ll MOD = 998244353;
constexpr ld eps = 1e-10;
constexpr ld pi = 3.1415926535897932;
template<class T>inline bool chmax(T& a, const T& b) { if (a < b) { a = b; return true; }return false; }
template<class T>inline bool chmin(T& a, const T& b) { if (a > b) { a = b; return true; }return false; }
inline void init() { cin.tie(nullptr); cout.tie(nullptr); ios::sync_with_stdio(false); cout << fixed << setprecision(15); }
template<class T>inline istream& operator>>(istream& is, vector<T>& v) { for (auto& a : v)is >> a; return is; }
template<class T>inline istream& operator>>(istream& is, deque<T>& v) { for (auto& a : v)is >> a; return is; }
template<class T, class U>inline istream& operator>>(istream& is, pair<T, U>& p) { is >> p.first >> p.second; return is; }
template<class T>inline vector<T> vec(size_t a) { return vector<T>(a); }
template<class T>inline vector<T> defvec(T def, size_t a) { return vector<T>(a, def); }
template<class T, class... Ts>inline auto vec(size_t a, Ts... ts) { return vector<decltype(vec<T>(ts...))>(a, vec<T>(ts...)); }
template<class T, class... Ts>inline auto defvec(T def, size_t a, Ts... ts) { return vector<decltype(defvec<T>(def, ts...))>(a, defvec<T>(def, ts...)); }
template<class T>inline void print(const T& a) { cout << a << "\n"; }
template<class T, class... Ts>inline void print(const T& a, const Ts&... ts) { cout << a << " "; print(ts...); }
template<class T>inline void print(const vector<T>& v) { for (int i = 0; i < v.size(); ++i)cout << v[i] << (i == v.size() - 1 ? "\n" : " "); }
template<class T>inline void print(const vector<vector<T>>& v) { for (auto& a : v)print(a); }
inline string reversed(const string& s) { string t = s; reverse(all(t)); return t; }

template<class Op> class SlidingWindowAggregation {
    using T = typename Op::T;
    stack<pair<T, T>> Front, Back;
public:
    bool empty() { return Front.empty() && Back.empty(); }
    size_t size() { return Front.size() + Back.size(); }
    T value() { 
        if (Front.empty())return Back.top().second;
        if (Back.empty())return Front.top().second;
        return Op::merge(Front.top().second, Back.top().second);
    }
    void push(T x) {
        if (Back.empty())Back.emplace(x, x);
        else Back.emplace(x, Op::merge(Back.top().second, x));
    }
    void pop() {
        if (Front.empty()) {
            Front.emplace(Back.top().first, Back.top().first);
            Back.pop();
            while (!Back.empty()) {
                Front.emplace(Back.top().first, Op::merge(Back.top().first, Front.top().second));
                Back.pop();
            }
        }
        Front.pop();
    }
    void clear() {
        while (!empty())pop();
    }
};
template<class Type> struct ll_max {
    using T = Type;
    inline static T merge(T vl, T vr) { return max(vl, vr); }
};

int main() {
    init();

    int n, k, m; cin >> n >> k >> m;
    VL a(n + 1);
    FOR(i, 0, n)cin >> a[i];
    rFOR(i, 0, n)a[i] += a[i + 1];
    auto dp = defvec<ll>(-LLINF, 2, n + 1);
    dp[0][0] = 0;
    SlidingWindowAggregation<ll_max<ll>> plus, minus;
    FOR(j, 0, k) {
        FOR(i, 0, n) {
            plus.push(dp[j & 1][i] + a[i]);
            if (m < plus.size())plus.pop();
            minus.push(dp[j & 1][i] - a[i]);
            if (m < minus.size())minus.pop();
            dp[(j + 1) & 1][i + 1] =
                max(plus.value() - a[i + 1], minus.value() + a[i + 1]);
        }
        plus.clear(), minus.clear();
    }
    print(dp[k & 1][n]);

    return 0;
}