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#include <bits/stdc++.h>
#define FOR(i, n) for(int i = 0; i < (n); ++i)
#define REP(i, a, b) for(int i = (a); i < (b); ++i)
#define TRAV(i, a) for(auto & i : (a))
#define SZ(x) ((int)(x).size())
#define X first
#define Y second
#define PR std::pair
#define MP std::make_pair
typedef long long ll;
typedef std::pair<int, int> PII;
typedef std::vector<int> VI;
#define WEZ(a, b) if((a) < (b)) a = b;

constexpr int N = 300'001;
constexpr int THRESH = 800;
constexpr int S = 400;
constexpr int MAX_M = 400;
int n, k, q;
ll big[S][N]; // TODO: czy mozna jakos zreinterpretowac pamiec na [N][S]? wtedy lepszy cache dla duzych k
ll(&arr)[N][S] = *reinterpret_cast<ll(*)[N][S]>(&big);
ll dp[N];
ll pref[N];
int A[N];
ll C[N];
PR<PII, int> Q[N];
ll ans[N];
ll straz_dp[N];
int straz[N];


void jazda(const int ind, int a){
	if(a > n) return;
	big[ind][a-1] = 0;
	REP(i, a, n+1){ // TODO: opt
		big[ind][i] = C[i] + (i-k >= a ? big[ind][i-k] : 0ll); // TODO: bez ifa powinno byc git
		if(big[ind][i-1] > big[ind][i]) big[ind][i] = big[ind][i-1];
	}
}
void jazda_straz(int a){
	if(a > n) return;
	straz_dp[a-1] = 0;
	REP(i, a, n+1){ // TODO: opt
		straz_dp[i] = C[i] + (i-k >= a ? straz_dp[i-k] : 0ll); // TODO: bez ifa powinno byc git
		if(straz_dp[i-1] > straz_dp[i]) straz_dp[i] = straz_dp[i-1];
	}
}
void jazda_dp(int a, int b){
	dp[a-1] = 0;
	REP(i, a, b+1){ // TODO: opt
		dp[i] = C[i] + (i-k >= a ? dp[i-k] : 0ll); // TODO: bez ifa powinno byc git
		if(dp[i-1] > dp[i]) dp[i] = dp[i-1];
	}
}

void duze(){
	// k > THRESH
	std::sort(Q, Q + q, [&](PR<PII, int> a, PR<PII, int> b){
		return (a.X.X - 1 + k) % k < (b.X.X - 1 + k) % k;
	});
	int M = std::min(MAX_M - 2, std::max(1, (int)std::sqrt(k) - 5));

	for(int s = 1; s <= n; s += k){ // TODO: od k
		int e = std::min(s + k - 1, n);
		for(int i = s; i <= e; ++i){
			if((i % k) % M == 0 || i == e){
				straz[i] = 1;
			}
		}

		for(int kt = 0; kt < q; ++kt){
			int a = Q[kt].X.X;
			int b = Q[kt].X.Y;
			int ind = Q[kt].Y;
			if(a > b) continue;
			if(a > e) continue;

			ll mx = 0;

			for(int i = a; i <= b; ++i){
				if(straz[i]){
					if(straz[i] != 2){
						jazda_straz(i); 
						straz[i] = 2;
					}
					WEZ(ans[ind], straz_dp[b] + mx);
					break;
				}

				mx = arr[ind][i-a];

				if(C[i] > 0) arr[ind][i-a] = arr[ind][i-a] + C[i];
				if(i > a && arr[ind][i-a-1] > arr[ind][i-a]) arr[ind][i-a] = arr[ind][i-a-1];
				WEZ(ans[ind], arr[ind][i-a]);
			}

			Q[kt].X.X += k;
		}
	}
}

void male(){
	// k <= THRESH
	std::sort(Q, Q + q);
	int M = std::max(1, std::max(1, (int)std::sqrt(n) + 1) * std::max(1, (int)std::sqrt(k) + 1));
	int qind = q-1;
	for(int s = n; s >= 1; s -= M){ // TODO: do k
		while(qind >= 0 && Q[qind].X.X > s) qind--;

		for(int ADD = 0; ADD < k; ADD += S){
			int UPTO = std::min(S, k - ADD);
			for(int off = 0; off < UPTO; ++off){
				jazda(off, s + 1 + ADD + off);
			}

			int qq = qind;
			for(int i = 0; i < M && s - i >= 1; ++i){
				int a = s - i;
				jazda_dp(a, s);

				while(qq >= 0 && Q[qq].X.X == a){
					int ind = Q[qq].Y;
					int b = Q[qq].X.Y;
					qq--;
					if(a > b) continue;

					if(b <= s){
						WEZ(ans[ind], dp[b]);
					}else{
						WEZ(ans[ind], dp[s]);
						if(s + 1 + ADD <= b){
							WEZ(ans[ind], big[0][b]);
						}

						// TODO: for (od, do) zamiast ifow
						for(int j = 0; j < UPTO && s + 1 + ADD + j <= b; ++j){
							int from = s + 1 + ADD + j;
							int moge = from - k;
							if(moge >= a){
								WEZ(ans[ind], big[j][b] + dp[moge]);
							}
						}
					}
				}
			}

		} // ADD
	}
}

int main() {
	std::ios_base::sync_with_stdio(false);
	std::cin.tie(0);

	std::cin >> n >> k >> q;
	FOR(i, n) std::cin >> A[i];
	FOR(i, n) pref[i+1] = pref[i] + A[i];
	REP(i, k, n+1) C[i] = pref[i] - pref[i-k];
	FOR(i, q){
		std::cin >> Q[i].X.X >> Q[i].X.Y;
		Q[i].X.X += k-1;
		Q[i].Y = i;
	}

	if(k <= THRESH){
		male();
	}else{
		duze();
	}

	FOR(i, q) std::cout << ans[i] << "\n";

	return 0;
}