#include<bits/stdc++.h>
using namespace std;
int n,m,ans,maxx,start=1;
int p[500005];
int main(){
//	freopen("P1714_2.in","r",stdin);
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++){
		scanf("%d",&p[i]);
		if(i-start+1>m){
			maxx-=p[start];
			start++;
		}
		maxx+=p[i];
		if(maxx>ans||i==1){
			ans=maxx;
			printf("%d~%d\n",start,i);
		}
		if(maxx<0){
			start=i+1;
			maxx=0;
		}
	}
	printf("%d",ans);
	return 0;
}