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#include <cstdio>
#include <cstdlib>
#include <cassert>

#include <algorithm>
#include <vector>

// Brute-force solution

struct query {
    int idx;
    int begin;
    int end;
};

int main() {
    int n, k, q;
    assert(3 == scanf("%d %d %d", &n, &k, &q));

    std::vector<long long int> soldiers;
    soldiers.reserve(n);
    std::vector<query> queries;
    queries.reserve(q);

    for (int i = 0; i < n; i++) {
        int x;
        assert(1 == scanf("%d", &x));
        soldiers.push_back(x);
    }

    for (int i = 0; i < q; i++) {
        int a, b;
        assert(2 == scanf("%d %d", &a, &b));
        queries.push_back({i, a - 1, b});
    }

    std::vector<long long int> d;
    std::sort(queries.begin(), queries.end(), [] (const query& q1, const query& q2) {
        if (q1.begin != q2.begin) {
            return q1.begin < q2.begin;
        }
        return q1.end < q2.end;
    });

    int last_begin = -1;
    long long int rolling_sum = 0;

    std::vector<long long int> answers;
    answers.resize(queries.size());

    for (const query& q : queries) {
        if (last_begin != q.begin) {
            last_begin = q.begin;
            d.clear();
            d.push_back(0);
            rolling_sum = 0;
            // printf("CLEARING\n");
        }

        while (q.begin + (int)d.size() <= q.end) {
            const int i = q.begin + (int)d.size();

            if ((int)d.size() > k) {
                rolling_sum -= soldiers[i - k - 1];
                // printf("REM SOLDIER %lld\n", soldiers[i - k - 1]);
            }
            rolling_sum += soldiers[i - 1];
            // printf("ADD SOLDIER %lld\n", soldiers[i - 1]);

            long long int best = d.back();
            if ((int)d.size() >= k) {
                best = std::max(best, rolling_sum + d[d.size() - k]);
            }
            // printf("ADDING %lld\n", best);
            d.push_back(best);
        }

        answers[q.idx] = d.back();
    }

    for (long long int a : answers) {
        printf("%lld\n", a);
    }

    return 0;
}