#include<iostream>
#include<cstdio>
#include<deque> 
using namespace std;
int read()
{
	int x,f=1;
	char ch;
	while(ch=getchar(),!isdigit(ch))if(ch=='-')f=-1;
	x=ch-48;
	while(ch=getchar(),isdigit(ch))x=x*10+ch-48;
	return x*f;
}
void write(int x)
{
	int cnt=0;char ch[50];
	while(ch[++cnt]=x%10+48,x/=10);
	while(putchar(ch[cnt]),--cnt);
	putchar('\n');
}
int sum[201000];
deque<int> q;
void push(int x)
{
	while(!q.empty()&&sum[x]>=sum[q.back()])q.pop_back();
	q.push_back(x);
}
int main()
{
	freopen("ggame.in","r",stdin);
	freopen("ggame.out","w",stdout);
	int n=read(),l=read(),r=read(),ans=-0x7f7f7f7f;
	for(int x,i=1;i<=n;i++)x=read(),sum[i]=sum[i-1]+x;
	for(int i=1;i<=r;i++)
	{
		push(i);
		if(i>=l)ans=max(ans,sum[i]);
	}
	for(int i=2;i<=n-l+1;i++)
	{
		while(!q.empty()&&q.front()-i<l-1)q.pop_front();
		ans=max(ans,sum[q.front()]-sum[i-1]);
		if(i+r<=n)push(i+r);
	}
	write(ans);
	fclose(stdin);
	fclose(stdout);
}