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// {{{
#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>

#define FOR(i, b, e) for (int i = (b); i <= (e); i++)
#define FORD(i, b, e) for (int i = (e); i >= (b); i--)
#define MP make_pair
#define FS first
#define ND second
#define PB push_back
#define ALL(x) x.begin(), x.end()

using namespace std;

using LL = long long;
using LD = long double;
using PII = pair<int,int>;
using PLL = pair<LL,LL>;
using PLD = pair<LD,LD>;
using VI = vector<int>;
using VLL = vector<LL>;
using VLD = vector<LD>;
using VB = vector<bool>;
using VS = vector<string>;
template<class T>
using V = vector<T>;
template<class T1, class T2>
using P = pair<T1,T2>;
template<class T,class Comp=greater<T>>
using PQ = priority_queue<T,V<T>,Comp>;

template<class T>
int sz(const T& a) { return (int)a.size(); }
template<class T>
void amin(T& a, T b) { a = min(a, b); }
template<class T>
void amax(T& a, T b) { a = max(a, b); }

/*
const size_t rseed =
  std::chrono::high_resolution_clock::now().time_since_epoch().count();
mt19937 rnd(rseed);
template<class T> T randint(T lo, T hi)
{
  return uniform_int_distribution<T>{lo,hi}(rnd);
}
*/

/* find_by_order(k) - k'th largest counting from 0;
   order_of_key(k) - number of items strictly smaller than k;
   join(other), split(k, other) - all keys in other greater than in *(this). */
template<class K,class V,class Comp=less<K>>
using ordered_map = __gnu_pbds::tree<K,V,Comp,
      __gnu_pbds::rb_tree_tag,__gnu_pbds::tree_order_statistics_node_update>;
template<class T,class Comp=less<T>>
using ordered_set = ordered_map<T,__gnu_pbds::null_type,Comp>;

const int inf = 1e9 + 1;
const LL infl = 1e18 + 1;

void solve();
// }}}

int main()
{
  int t = 1;
  // scanf("%d", &t);
  FOR(i, 1, t) {
    // printf("Case #%d: ", i);
    solve();
  }
}

const int N = 3e5;
int n, k, q;
LL a[N + 1], dp[N + 1];

struct Q
{
  int l, r;
  LL ans;
};

Q qr[N + 1];

void rec(int lo, int hi, VI v)
{
  if (hi - lo <= 2 * k) {
    FOR(i, 0, sz(v) - 1) {
      FOR(j, qr[v[i]].l, qr[v[i]].r) {
        dp[j] = max(0ll, a[j]);
        if (j > qr[v[i]].l) amax(dp[j], dp[j - 1]);
        if (j >= qr[v[i]].l + k) amax(dp[j], dp[j - k] + a[j]);
      }
      amax(qr[v[i]].ans, dp[qr[v[i]].r]);
      // fprintf(stderr, "A %d -> %lld\n", v[i], qr[v[i]].ans);
    }
    return;
  }

  int mid = (lo + hi) / 2;

  VI vl, vr;
  for (int i = 0; i < sz(v); ) {
    if (qr[v[i]].r <= mid) {
      vl.PB(v[i]);
      swap(v[i], v.back());
      v.pop_back();
    }
    else if (qr[v[i]].l >= mid + 1) {
      vr.PB(v[i]);
      swap(v[i], v.back());
      v.pop_back();
    }
    else {
      i++;
    }
  }

  FOR(d, 0, k - 1) {
    FOR(i, mid + 1 - d, hi) {
      dp[i] = max(0ll, a[i]);
      if (i > mid + 1 - d) amax(dp[i], dp[i - 1]);
      if (i > mid - d + k) amax(dp[i], dp[i - k] + a[i]);
    }

    FORD(i, lo, mid - d) {
      dp[i] = 0;
      if (i < mid - d) amax(dp[i], dp[i + 1]);
      if (i < mid - d - k + 1) amax(dp[i], dp[i + k] + a[i]);
      if (i == mid - d - k + 1) amax(dp[i], a[i]);
    }

    FOR(i, 0, sz(v) - 1) {
      if (qr[v[i]].l <= mid - d) {
        amax(qr[v[i]].ans, dp[qr[v[i]].l] + dp[qr[v[i]].r]);
      }
      else if (qr[v[i]].l == mid + 1 - d) {
        amax(qr[v[i]].ans, dp[qr[v[i]].r]);
      }
    }

    /*
    FOR(i, lo, hi) {
      printf("%lld ", dp[i]);
    }
    putchar('\n');
    */
  }

  /*
  FOR(i, 0, sz(v) - 1) {
    fprintf(stderr, "B %d -> %lld\n", v[i], qr[v[i]].ans);
  }
  */

  rec(lo, mid, vl);
  rec(mid + 1, hi, vr);
}

void solve()
{
  scanf("%d %d %d", &n, &k, &q);
  // fprintf(stderr, "n=%d k=%d q=%d\n", n, k, q);

  FOR(i, 1, n) {
    scanf("%lld", &a[i]);
    dp[i] = dp[i - 1] + a[i];
  }

  n -= k - 1;

  FOR(i, 1, n) {
    a[i] = dp[i + k - 1] - dp[i - 1];
  }

  VI v;
  FOR(i, 1, q) {
    scanf("%d %d", &qr[i].l, &qr[i].r);
    qr[i].r -= k - 1;
    if (qr[i].l <= qr[i].r) {
      v.PB(i);
    }
  }

  rec(1, n, v);

  FOR(i, 1, q) {
    printf("%lld\n", qr[i].ans);
  }
}