#include <atcoder/segtree>
#include <bits/stdc++.h>

using namespace std;
using ll = long long;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)

ll op(ll a, ll b) {
    return max(a, b);
}

ll e() {
    return 0;
}

int main() {
    cin.tie(nullptr);
    ios_base::sync_with_stdio(false);
    int n, b, c;
    cin >> n >> b >> c;
    b--;
    c--;
    vector<ll> a(n + 1, 0);
    rep(i, n) cin >> a[i];
    for (int i = n; i > 0; i--)
        a[i - 1] += a[i];
    atcoder::segtree<ll, op, e> seg1(n + 1), seg2(n + 1);
    seg2.set(0, a[0]);
    for (int i = 1; i <= n; i++) {
        seg1.set(i, seg2.prod(max(0, i - c), i) - a[i]);
        seg2.set(i, seg1.prod(max(0, i - b), i) + a[i]);
    }

    cout << max(seg1.get(n), seg2.get(n)) << endl;
    return 0;
}