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#include <algorithm>
#include <set>
#include <map>
#include <vector>
#include <unordered_map>
#include <cstdio>

#define ll long long
#define PII pair<int, int>

using namespace std;

int n,k,qs;
ll a[300000];
vector<PII> q;
ll res[300000];
ll s[300000];
ll v[300000];
vector<int> clusters;
unordered_map<int, ll*> dp;
set<int> availableDp;

void computeSum() {
  ll sum = 0;
  for(int i=0;i<k;i++) {
    s[i] = 0;
    sum += a[i];
  }
  s[k-1] = sum;
  for(int i=k;i<n;i++) {
    sum += a[i]-a[i-k];
    s[i] = sum;
  }
}

void selectClusters(int lastFrom) {
  set<int> selected;
  int chunks = 27;
  for(int i=0;i<chunks;i++) {
    selected.insert((i*lastFrom)/chunks);
  }
  int p = 0;
  for(auto sel : selected) {
    clusters.push_back(sel);
  }
}

void computeDp(ll* d, int start, int end) {
  int len = end - start + 1;
  d[k - 1] = max(0LL, s[start + k - 1]);
  for(int i=k;i<len;i++) {
    ll best1 = 0;
    for(int j=0;j<k;j++) {
      if(i - j - k >= 0) {
        best1 = max(best1, d[i - j - k]);
      }
    }
    best1 += max(0LL, s[start + i]);
    ll best2 = best1;
    for(int j=0;j<k-1;j++) {
      best2 = max(best2, d[i - j - 1]);
    }
    d[i] = max(best1, best2);
  }
}

void startDp() {
  int lastFrom = -1;
  int lastTo = -1;
  for(auto qe : q) {
    lastFrom = max(lastFrom, qe.first);
    lastTo = max(lastTo, qe.second);
  }
  selectClusters(lastFrom);
  for(auto lastLeft : clusters) {
    if(lastLeft + 2*k <= lastTo) {
      for(int i=0;i<k;i++) {
        int start = lastLeft + i;
        if(dp.find(start) == dp.end()) {
          ll* d = new ll[lastTo - start + 1];
          fill(d, d+k-1, 0LL);
          computeDp(d, start, lastTo);
          dp[start] = d;
        }
      }
    }
  }
}

void computeAvailableDp() {
  vector<int> keys;
  for(auto it=dp.begin();it!=dp.end();it++) {
    keys.push_back(it->first);
  }
  sort(keys.begin(), keys.end(), greater<int>());

  int prev = -1;
  int consecutive = 0;
  for(auto cur: keys) {
    if(cur == prev - 1) {
      consecutive++;
      if(consecutive >= k-1) {
        availableDp.insert(cur);
      }
    } else {
      consecutive = 0;
    }
    prev = cur;
  }
}

ll solveRange(int from, int to) {
  if (to - from + 1 < k) {
    return 0;
  }
  auto f = availableDp.lower_bound(from);
  bool useDp = false;
  int dpStart = -1;
  int last = 0;
  if(f != availableDp.end()) {
    useDp = (*f) < (to - k);
    dpStart = *f;
  }
  if(useDp) {
    last = (*f) + k - 1;
  } else {
    last = to;
  }
  computeDp(v, from, last);
  if(useDp) {
    ll res = 0;
    for(int i=0;i<k;i++) {
      ll* d = dp[dpStart+i];
      ll d1 = d[to - (dpStart+i)];
      int ix = last - from - k + i;
      ll d2 = (ix<0)?0:v[ix];
      res = max(res, d1 + d2);
    }
    return res;
  }
  return v[last - from];
}

bool qcmp(int a, int b) {
  return ((q[a].first < q[b].first) || ((q[a].first == q[b].first) && (q[a].second < q[b].second)));
}

void solve() {
  computeSum();
  startDp();
  computeAvailableDp();
  int r[qs];
  for(int i=0;i<qs;i++) {
    r[i] = i;
  }
  sort(r, r + qs, qcmp);
  for(int i=0;i<qs;i++) {
    res[r[i]] = solveRange(q[r[i]].first, q[r[i]].second);
  }
}

int main(int argc, char** argv) {
  int from, to;
  scanf("%d%d%d", &n, &k, &qs);
  for(int i=0;i<n;i++) {
    scanf("%lld", &(a[i]));
  }
  for(int i=0;i<qs;i++) {
    scanf("%d%d", &from, &to);
    q.push_back(make_pair(from-1, to-1));
  }
  solve();
  for(int i=0;i<qs;i++) {
    printf("%lld\n", res[i]);
  }
  return 0;
}