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#include <bits/stdc++.h>
using namespace std;
#define rep(i,a,n) for (int i=a;i<n;i++)
#define per(i,a,n) for (int i=n-1;i>=a;i--)
#define pb push_back
#define mp make_pair
#define all(x) (x).begin(),(x).end()
#define fi first
#define se second
#define SZ(x) ((int)(x).size())
typedef vector<int> VI;
typedef long long ll;
typedef pair<int,int> PII;
typedef double db;
const ll mod=1000000007;
ll powmod(ll a,ll b) {ll res=1;a%=mod; assert(b>=0); for(;b;b>>=1){if(b&1)res=res*a%mod;a=a*a%mod;}return res;}
ll gcd(ll a,ll b) { return b?gcd(b,a%b):a;}
// head

const int N=301000;
int n,k,q,a[N],l[N],r[N];
ll s[N],val[N],ans[N],dp[N];

void solve(int l,int r,vector<int> id) {
	if (r-l<k) {
		return;
	} else {
		int mid=(l+r)>>1;
		VI ql,qr,qmid;
		for (auto x:id) {
			if (::r[x]<=mid) ql.pb(x);
			else if (::l[x]>=mid) qr.pb(x);
			else qmid.pb(x);
		}
		solve(l,mid,ql);
		solve(mid,r,qr);
		dp[mid]=0;
		for (int j=mid-1;j>=l;j--) {
			dp[j]=dp[j+1];
			if (j+k<=mid) dp[j]=max(dp[j],dp[j+k]+val[j]);
		}
		for (int j=mid+1;j<=r;j++) {
			dp[j]=dp[j-1];
			if (j-k>=mid) dp[j]=max(dp[j],dp[j-k]+val[j-k]);
		}
		for (auto y:qmid) ans[y]=max(ans[y],dp[::l[y]]+dp[::r[y]]);
		rep(i,l,r+1) dp[i]=0;
		for (int x=mid-1;x>mid-k;x--) {
			dp[x]=0; 
			if (x-k+1>=l) dp[x-k+1]=0;
			for (int j=x-k;j>=l;j--) {
				dp[j]=max(dp[j+1],dp[j+k]+val[j]);
			}
			dp[x+k]=0;
			for (int j=x+k+k;j<=r;j++) {
				dp[j]=max(dp[j-1],dp[j-k]+val[j-k]);
			}
			for (auto y:qmid) {
				if (::l[y]<=x&&x+k<=::r[y]) ans[y]=max(ans[y],dp[::l[y]]+dp[::r[y]]+val[x]);
			}
		}
	}
}

const int T=2521,T2=300000/T+5;
ll pd[T2][N];
int ty[N],nxt[N];
VI que[N];
int main() {
	scanf("%d%d%d",&n,&k,&q);
	rep(i,1,n+1) scanf("%d",a+i),s[i]=a[i]+s[i-1];
	for (int i=0;i+k<=n;i++) {
		val[i]=max(s[i+k]-s[i],0ll);
	}
	VI v;
	rep(i,0,q) {
		scanf("%d%d",l+i,r+i); --l[i];
		que[r[i]].pb(i);
		v.pb(i);
	}
	if (k<=T) {
		solve(0,n,v);
	} else {
		int B=100;
		for (int rem=0;rem<k;rem+=B) {
			int np=n+1;
			per(i,0,n+1) {
				if (i%k==rem) ty[i]=1;
				else if (i%k>rem&&i%k<rem+B) ty[i]=-1;
				else ty[i]=-2;
				nxt[i]=np;
				if (ty[i]!=-2) np=i;
			}

			int v=0;
			for (int x=rem;x<=n;x+=k) {
				pd[v][x]=0;
				per(j,0,x) {
					pd[v][j]=pd[v][j+1];
					if (j+k<=x) pd[v][j]=max(pd[v][j],val[j]+pd[v][j+k]);
				}
				ty[x]=v;
				v++;
			}
			for (int z=rem;z<rem+B&&z<k;z++) {
				for (int y=z;y<=n;y+=k) {
					for (auto q:que[y]) {
						int vl=l[q],px=vl;
						if (ty[px]==-2) px=nxt[px];
						while (px<=y) {
							if (ty[px]>=0) dp[px]=pd[ty[px]][vl];
							else {
								if (px==vl) {
									dp[px]=0;
								} else {
									dp[px]=dp[px-1];
									if (px-k>=vl) {
										dp[px]=max(dp[px],dp[px-k]+val[px-k]);
									}
								}
							}
							px=nxt[px];
						}
						ans[q]=dp[y];
					}
				}
			}
		}
	}
	rep(i,0,q) printf("%lld\n",ans[i]);
}