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#include <bits/stdc++.h>

using namespace std;

#define sim template < class c
#define ris return * this
#define dor > debug & operator <<
#define eni(x) sim > typename \
enable_if<sizeof dud<c>(0) x 1, debug&>::type operator<<(c i) {
sim > struct rge { c b, e; };
sim > rge<c> range(c i, c j) { return {i, j}; }
sim > auto dud(c* x) -> decltype(cerr << *x, 0);
sim > char dud(...);
struct debug {
#ifdef LOCAL
~debug() { cerr << endl; }
eni(!=) cerr << boolalpha << i; ris; }
eni(==) ris << range(begin(i), end(i)); }
sim, class b dor(pair < b, c > d) {
  ris << "(" << d.first << ", " << d.second << ")";
}
sim dor(rge<c> d) {
  *this << "[";
  for (c it = d.b; it != d.e; ++it)
    *this << ", " + 2 * (it == d.b) << *it;
  ris << "]";
}
#else
sim dor(const c&) { ris; }
#endif
};
#define imie(x...) " [" #x ": " << (x) << "] "

#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
template <typename A, typename B>
using unordered_map2 = __gnu_pbds::gp_hash_table<A, B>;
using namespace __gnu_pbds;
template <typename T> using ordered_set =
  __gnu_pbds::tree<T, __gnu_pbds::null_type, less<T>, __gnu_pbds::rb_tree_tag,
                   __gnu_pbds::tree_order_statistics_node_update>;
// ordered_set<int> s; s.insert(1); s.insert(2);
// s.order_of_key(1);    // Out: 0.
// *s.find_by_order(1);  // Out: 2.

using ld = long double;
using ll = long long;

constexpr int mod = 1000 * 1000 * 1000 + 7;
constexpr int odw2 = (mod + 1) / 2;

void OdejmijOd(int& a, int b) { a -= b; if (a < 0) a += mod; }
int Odejmij(int a, int b) { OdejmijOd(a, b); return a; }
void DodajDo(int& a, int b) { a += b; if (a >= mod) a -= mod; }
int Dodaj(int a, int b) { DodajDo(a, b); return a; }
int Mnoz(int a, int b) { return (ll) a * b % mod; }
void MnozDo(int& a, int b) { a = Mnoz(a, b); }
int Pot(int a, ll b) { int res = 1; while (b) { if (b % 2 == 1) MnozDo(res, a); a = Mnoz(a, a); b /= 2; } return res; }
int Odw(int a) { return Pot(a, mod - 2); }
void PodzielDo(int& a, int b) { MnozDo(a, Odw(b)); }
int Podziel(int a, int b) { return Mnoz(a, Odw(b)); }
int Moduluj(ll x) { x %= mod; if (x < 0) x += mod; return x; }

template <typename T> T Maxi(T& a, T b) { return a = max(a, b); }
template <typename T> T Mini(T& a, T b) { return a = min(a, b); }

constexpr int nax = 300 * 1000 + 105;

ll wyniki[nax];

struct Query {
  int a, b;
  int id;
};

debug& operator<<(debug& deb, const Query& q) {
  #ifdef LOCAL
  return deb << "Query([" << q.a << ", " << q.b << "], " << q.id << ")";
  #else
  return deb;
  #endif
}

int n, k;
ll tab[nax];
ll dp[nax];

void Divide(int a, int b, const vector<Query>& queries) {
  if (queries.empty()) return;
  if (a == b) {
    for (const Query& q : queries) {
      wyniki[q.id] = tab[a];
    }
    return;
  }
  vector<Query> lewo, prawo, tutaj;
  const int s = (a + b + 1) / 2;
  int min_a = s - 1, max_b = s;
  for (const Query& q : queries) {
    if (q.b < s) {
      lewo.push_back(q);
    } else if (q.a >= s) {
      prawo.push_back(q);
    } else {
      tutaj.push_back(q);
      Mini(min_a, q.a);
      Maxi(max_b, q.b);
    }
  }
  Divide(a, s - 1, lewo);
  Divide(s, b, prawo);
  if (tutaj.empty()) return;
  //debug() << imie(a) imie(b) imie(tutaj) imie(s);
  for (int L = 0; L < k; L++) {
    const int R = k - 1 - L;
    const int lo = s - 1 - L;
    const int ro = s + R;
    //debug() << imie(L) imie(R) imie(lo) imie(ro);
    for (int i = lo; i >= min_a; i--) {
      dp[i] = tab[i];
      if (i + 1 <= lo) Maxi(dp[i], dp[i + 1]);
      if (i + k <= lo) Maxi(dp[i], dp[i + k] + tab[i]);
      //debug() << imie(i) imie(dp[i]);
    }
    for (int i = ro; i <= max_b; i++) {
      dp[i] = tab[i];
      if (i - 1 >= ro) Maxi(dp[i], dp[i - 1]);
      if (i - k >= ro) Maxi(dp[i], dp[i - k] + tab[i]);
      //debug() << imie(i) imie(dp[i]);
    }
    for (const Query& q : tutaj) {
      ll wyn = 0;
      if (q.a <= lo) wyn += dp[q.a];
      if (q.b >= ro) wyn += dp[q.b];
      Maxi(wyniki[q.id], wyn);
    }
  }
}

void Run(const vector<Query>& queries) {
  //debug() << imie(n) imie(k) imie(range(tab, tab + n));
  //debug() << imie(queries);
  Divide(0, n - 1, queries);
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr);
  int q;
  cin >> n >> k >> q;
  assert(1 <= n and n <= 300 * 1000);
  assert(1 <= q and q <= 300 * 1000);
  assert(1 <= k and k <= n);
  for (int i = 1; i <= n; i++) {
    cin >> tab[i];
    assert(-1000 * 1000 * 1000 <= tab[i] and tab[i] <= 1000 * 1000 * 1000);
    tab[i] += tab[i - 1];
  }
  vector<ll> nowe;
  for (int i = k; i <= n; i++) {
    nowe.push_back(max(0ll, tab[i] - tab[i - k]));
  }
  nowe.push_back(0ll);
  vector<Query> queries(q);
  for (int i = 0; i < q; i++) {
    queries[i].id = i;
    int& a = queries[i].a;
    int& b = queries[i].b;
    cin >> a >> b;
    assert(1 <= a and a <= b and b <= n);
    a--;
    b -= k;
    if (a > b) {
      a = b = (int) nowe.size() - 1;
    }
  }
  n = (int) nowe.size();
  for (int i = 0; i < n; i++) {
    tab[i] = nowe[i];
  }
  Run(queries);
  for (int i = 0; i < q; i++) {
    cout << wyniki[i] << "\n";
  }
  return 0;
}