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#include <bits/stdc++.h>
#define REP(i,n) for (int _n=(n), i=0;i<_n;++i)
#define FOR(i,a,b) for (int i=(a),_b=(b);i<=_b;++i)
using std::int64_t;

void init_io() {
  std::cin.tie(nullptr);
  std::ios::sync_with_stdio(false);
}

struct Query {
  int index = 0;
  int endpoint[2] = {};

  int cost() const { return endpoint[1] - endpoint[0] + 1; }
};

int group_size;
std::vector<Query> queries;
std::vector<Query> queries_by_endpoint[2];
std::vector<int64_t> group_value;
std::vector<int64_t> answers;

void read_input() {
  int n, num_queries;
  std::cin >> n >> group_size >> num_queries;

  std::vector<int> value;
  value.reserve(n);
  REP(i, n) {
    int x;
    std::cin >> x;
    value.push_back(x);
  }

  group_value.reserve(n - group_size + 1);
  int64_t gv = 0;
  REP(i, group_size) gv += value[i];
  group_value.push_back(gv);
  FOR(i, group_size, n-1) {
    gv += value[i];
    gv -= value[i - group_size];
    group_value.push_back(gv);
  }

  queries.reserve(num_queries);
  answers.assign(num_queries, 0);
  REP(i, num_queries) {
    Query query;
    query.index = i;
    std::cin >> query.endpoint[0] >> query.endpoint[1];
    query.endpoint[0] -= 1;
    query.endpoint[1] -= group_size;
    if (query.endpoint[1] >= query.endpoint[0]) {
      queries.push_back(query);
    }
  }
}

struct QueriesAtEndpoint {
  int64_t total_cost = 0;
  std::vector<Query> queries;
};

struct PQEntry {
  int endpoint = 0;
  int position = 0;
  int64_t total_cost = 0;
};

inline bool operator<(const PQEntry &a, const PQEntry &b) {
  return a.total_cost < b.total_cost;
}

void sort_queries() {
  REP(i,2) {
    queries_by_endpoint[i].reserve(queries.size());
  }

  std::vector<char> unallocated(answers.size(), 0);

  int n = group_value.size();
  std::vector<QueriesAtEndpoint> queries_at_endpoint[2];
  REP(i,2) queries_at_endpoint[i].resize(n);

  for (const Query &query: queries) {
    unallocated[query.index] = 1;
    REP(i,2) {
      auto &qe = queries_at_endpoint[i][query.endpoint[i]];
      qe.total_cost += query.cost();
      qe.queries.push_back(query);
    }
  }

  std::priority_queue<PQEntry> pq;
  REP(i, 2) REP(x, n) {
    const QueriesAtEndpoint &qe = queries_at_endpoint[i][x];
    if (qe.total_cost > 0) {
      PQEntry pq_entry;
      pq_entry.endpoint = i;
      pq_entry.position = x;
      pq_entry.total_cost = qe.total_cost;
      pq.push(pq_entry);
    }
  }

  while (!pq.empty()) {
    PQEntry pq_entry = pq.top();
    pq.pop();
    QueriesAtEndpoint &qe = queries_at_endpoint[pq_entry.endpoint][pq_entry.position];
    if (qe.total_cost != pq_entry.total_cost) continue;
    const int endpoint2 = pq_entry.endpoint ^ 1;
    for (const Query &q : qe.queries) {
      if (unallocated[q.index]) {
        queries_by_endpoint[pq_entry.endpoint].push_back(q);
        unallocated[q.index] = 0;

        const int x2 = q.endpoint[endpoint2];
        QueriesAtEndpoint &qe2 = queries_at_endpoint[endpoint2][x2];
        qe2.total_cost -= q.cost();
        if (qe2.total_cost > 0) {
          PQEntry pq_entry2;
          pq_entry2.endpoint = endpoint2;
          pq_entry2.position = x2;
          pq_entry2.total_cost = qe2.total_cost;
          pq.push(pq_entry2);
        }
      }
    }
    qe.queries.clear();
    qe.total_cost = 0;
  }
}

std::vector<int64_t> solution;

void generate_solution(const int start, const int to) {
  int64_t sol = 0;
  int limit = std::min(start + group_size - 1, to);
  int i = start;
  while (i <= limit) {
    sol = std::max(sol, group_value[i]);
    solution[i] = sol;
    ++i;
  }
  while (i <= to) {
    sol = std::max(sol, group_value[i] + solution[i - group_size]);
    solution[i] = sol;
    ++i;
  }
}

void solve(const std::vector<Query> &queries_to_solve) {
  int n = group_value.size();
  solution.resize(n);
  auto it = queries_to_solve.begin();
  while (it != queries_to_solve.end()) {
    auto to = it->endpoint[1];
    auto jt = it + 1;
    while (jt != queries_to_solve.end() && it->endpoint[0] == jt->endpoint[0]) {
      to = std::max(to, jt->endpoint[1]);
      ++jt;
    }

    generate_solution(it->endpoint[0], to);

    while (it != jt) {
      auto answer = solution[it->endpoint[1]];
      answers[it->index] = answer;
      ++it;
    }
  }
}

void print_answers() {
  for (auto answer : answers) {
    std::cout << answer << '\n';
  }
}

int main() {
  init_io();
  read_input();

  sort_queries();

  solve(queries_by_endpoint[0]);

  std::reverse(group_value.begin(), group_value.end());
  int n = group_value.size();
  for (Query &query : queries_by_endpoint[1]) {
    std::swap(query.endpoint[0], query.endpoint[1]);
    REP(i,2) query.endpoint[i] = n-1-query.endpoint[i];
  }

  solve(queries_by_endpoint[1]);

  print_answers();
}