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///MEMENTO MEMO, MEMENTO LONG LONG
#include <bits/stdc++.h>

#define DEBUG if(0)
#define COUT cout << "\e[36m"
#define ENDL "\e[39m" << endl
#define VAR(v) " [\e[32m" << #v << "\e[36m=\e[91m" << v << "\e[36m] "

using namespace std;

typedef long long LL;

int n, k, q;
vector<int> nums;

vector<tuple<int, int, int>> queries;

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cin >> n >> k >> q;
    nums.resize(n);

    for (int i = 0; i < n; ++i)
    {
        cin >> nums[i];
    }
    queries.resize(q);
    for (int i = 0; i < q; ++i)
    {
        cin >> get<0>(queries[i]) >> get<1>(queries[i]);
        get<0>(queries[i])--;
        get<1>(queries[i])--;
        get<1>(queries[i]) *= -1;
        get<2>(queries[i]) = i;
    }
    sort(queries.begin(), queries.end());

    vector<LL> ksum(n);
    for (int i = 0; i < n; ++i)
    {
        ksum[i] = nums[i] + (i>0 ? ksum[i-1] : 0) - (i-k >= 0 ? nums[i-k] : 0);
    }
    DEBUG
    {
        DEBUG COUT << "ksum ";
        for(auto el : ksum)
        {
            COUT << el  << " ";
        }
        COUT << ENDL;
    };


    int calced_b = -1;
    vector<LL> dp(n);
    vector<LL> ans(q);
    for(auto& query : queries)
    {
        int b = get<0>(query), e = -get<1>(query);

        if(calced_b < b)
        {
            calced_b = b;
            for (int i = b; i <= e; ++i)
            {
                dp[i] = 0;
                if(i-k+1 >= b)
                {
                    dp[i] = max(dp[i], ksum[i] + ((i-k >= b)? dp[i-k] : 0));
                }
                if(i-1 >= b)
                {
                    dp[i] = max(dp[i], dp[i-1]);
                }
            }
        }
        ans[get<2>(query)] = dp[e];

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