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#include <bits/stdc++.h>

using namespace std;

long long result = 0LL;

void rec(int l, int r, const int &k, const vector<long long> &a, vector<long long> &ps, const long long res) {
    if((r - l + 1) < k) {
        return;
    }

    long long s = 0;
    for(int i = l; i < l + k; i++) {
        s += a[i];
    }
    result = max(result, res + s);
    rec(l + k, r, k, a, ps, res + s);
    for(int i = l + 1; i <= r; i++) {
        if((r - i + 1) >= k) {
            rec(i, r, k, a, ps, res);
        }
    }
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, k, q;
    cin >> n >> k >> q;

    vector<long long> a(n + 1);
    vector<long long> ps(n + 1);
    for(int i = 1; i <= n; i++) {
        cin >> a[i];
        ps[i] = ps[i - 1] + a[i];
    }

    while(q--) {
        int l, r;
        cin >> l >> r;

        result = 0;
        rec(l, r, k, a, ps, 0LL);
        cout << result << "\n";
    }

    return 0;
}