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#include <iostream>
#include <vector>
#include <algorithm>

using namespace std;

int n, k, q;

struct query {
    int a;
    int b;
    int id;

    bool operator<(const query& other) const {
        if (a == other.a) {
            return b > other.b;
        }
        return a < other.a;
    }
};

bool appeared_start[300001];
bool appeared_end[300001];
long as[300001];
long str_ending_at[300001];
long str_upto[300001];
long str_so_far = 0;
long ans[300001];

int main() {
    cin >> n >> k >> q;
    vector<query> queries;
    for (int i = 0; i < n; ++i) {
        cin >> as[i];
    }

    for (int i = 0; i < q; ++i) {
        int a,b;
        cin >> a >> b;
        if (b - a + 1 < k) {
            ans[i] = 0;
        } else {
            appeared_start[a-1] = 1;
            appeared_end[b-1] = 1;
            query x{a - 1, b - 1, i};
            queries.push_back(x);
        }
    }

    int total_start = 0;
    int total_end = 0;
    for (int i = 0; i < n; ++i) {
        total_start += appeared_start[i];
        total_end += appeared_end[i];
    }

//    for (int i = 0; i < n; ++i) {
//        cerr << as[i] << " ";
//    }
//
//    cerr << endl;

     if (total_end < total_start) {
//      if (false) {
        // reverse the table and all queries
        reverse(as, as+n);

        for(int i = 0; i < queries.size(); ++i) {
            int olda = queries[i].a;
            int oldb = queries[i].b;
            queries[i].a = n - oldb - 1;
            queries[i].b = n - olda - 1;
        }
    }

//    for (int i = 0; i < n; ++i) {
//        cerr << as[i] << " ";
//    }
//
//    cerr << endl;

    for (int i = 0; i < n; ++i) {
        str_so_far += as[i];
        str_upto[i] = str_so_far;
    }
    str_ending_at[k-1] = str_upto[k-1];
    for (int i = k; i < n; ++i) {
        str_ending_at[i] = str_upto[i] - str_upto[i-k];
    }

    sort(queries.begin(), queries.end());

//    for (int i = 0; i < queries.size(); ++i) {
//        cerr << queries[i].id << ": " << queries[i].a << " " << queries[i].b << endl;
//    }

    long res_upto[n];
    for(int i = 0; i < k-1; ++i) {
        res_upto[i] = 0;
    }
    int lasta = -1;
    for (int i = 0; i < queries.size(); ++i) {
        // count only needed values
        // can be optimized to re-use values after K
        int a = queries[i].a;
        int b = queries[i].b;
        if (queries[i].a != lasta) {
            res_upto[k-1] = max(0L, str_ending_at[a+k-1]);
            // cerr << "UPTO " << k-1 << ": " << res_upto[k-1] << endl;
            for (long j = a+k; j <= b; ++j) {
                res_upto[j - a] = max(res_upto[j - a - k] + str_ending_at[j], res_upto[j - a - 1]);
                // cerr << "UPTO    " << j-a << ": " << res_upto[j-a] << endl;
                // cerr << "UPTO_pr " << res_upto[j-a-k] << "; STR_end " << str_ending_at[j] << endl;
            }
            lasta = queries[i].a;
        }
        ans[queries[i].id] = res_upto[b-a];
    }

    for (int i = 0; i < q; ++i) {
        cout << ans[i] << endl;
    }

    return 0;
}