// compile: make data
// run: ./data < data.in
#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#ifdef LOCAL
#include <debug/codeforces.h>
#define debug(x...) _debug_print(#x, x);
#define Debug(x...) _debug_print_format(#x, x);
std::ifstream terminal("/dev/tty");
#define PP cerr<<"\033[1;30mpause...\e[0m",terminal.ignore();
#else
#define debug(x...)
#define Debug(x...)
#define PP
#endif
template<typename...Args> void print_(Args...args){((cout<<args<<" "),...)<<endl;}
#define rep(i,a,b) for(int i=(a);i<(int)(b);++i)
#define sz(v) ((int)(v).size())
#define print(...) print_(__VA_ARGS__);
#define FIND(a, x) ((find(a.begin(),a.end(),(x))!=a.end())?1:0)
#define cmin(x,...) x=min({(x),__VA_ARGS__})
#define cmax(x,...) x=max({(x),__VA_ARGS__})
#define INTMAX (int)(9223372036854775807)
#define INF (int)(1152921504606846976)
#define NaN (int)(0x8b88e1d0595d51d1)
#define double long double
#define int long long
#define uint unsigned long long
#define MAXN 200010

struct STmin {
    vector<int> a;
    vector<vector<int>> dp;
    STmin(vector<int> v) {
        a = v;
        build();
    }
    void build() {
        int logn = log2(sz(a)) + 2;
        dp.assign(sz(a), vector<int>(logn, 0));
        rep(i, 0, sz(a)) dp[i][0] = a[i];
        rep(j, 1, logn) {
            rep(i, 0, sz(a)) {
                dp[i][j] = min(dp[i][j-1], dp[min(i + (1 << (j-1)), sz(a)-1)][j-1]);
            }
        }
    }
    int query(int l, int r) {
        int j = log2(r - l + 1);
        return min(dp[l][j], dp[r - (1 << j) + 1][j]);
    }
};

int32_t main() {
    ios::sync_with_stdio(false); cin.tie(nullptr); cout.tie(nullptr);

    int n, A, B; cin >> n >> A >> B;
    vector<int> a(n+1), sum(n+1, 0);
    rep(i, 1, n+1) cin >> a[i];
    rep(i, 1, n+1) sum[i] = sum[i-1] + a[i];
    STmin st(sum);
    int ans = -INF;
    rep(i, A, n+1) cmax(ans, sum[i] - st.query(max(i-B, 0ll), i-A));
    cout << ans << endl;

    return 0;
}