#include<iostream>
#include<cassert>
#include<atcoder/segtree>
using namespace std;
long op(long a,long b){return min(a,b);}
long e(){return(long)1e18;}
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(nullptr);
	int N,B,C;cin>>N>>B>>C;
	long sum=0;
	atcoder::segtree<long,op,e>seg(N+1);
	seg.set(0,0L);
	for(int i=0;i<N;i++)
	{
		int A;cin>>A;
		sum+=A;
		int l=max(0,i-C+1);
		if(B>2||i==0)seg.set(i+1,seg.prod(l,i+1)+A);
		else seg.set(i+1,seg.prod(l,i)+A);
	}
	cout<<sum-seg.prod(max(N-C+1,0),N+1)<<endl;
}