rt，这是《深进》中的代码，交上去 $0$ 分。

#include<bits/stdc++.h>
using namespace std;
const int maxn=100010;
typedef long long ll;
ll f[2][maxn],pre[210][maxn];
int h,t,n,k,a[maxn];
struct vec{
	int id,x;
	ll y;
	ll operator()(int v){
		return x*v+y;
	}
}q[maxn];
ll cross(vec a,vec b,vec c){
	a.x-=b.x,a.y-=b.y,b.x-=c.x,b.y-=c.y;
	return b.x*a.y-a.x*b.y;
} 
int main(){
	cin>>n>>k;
	for(int i=1;i<=n;++i){
		cin>>a[i],a[i]+=a[i-1];
	}	
	for(int T=1;T<=k;++T){
		h=t=0;
		q[0]=(vec){0,0,0};
		for(int i=1;i<=n;++i){
			while(h<t&&q[h](a[i])<=q[h+1](a[i]))++h;
			f[T&1][i]=q[h](a[i]);
			pre[T][i]=q[h].id;
			vec x=(vec){i,a[i],f[T&1^1][i]-(ll)a[i]*a[i]};
			while(h<t&&cross(q[t-1],q[t],x)<=0)--t;
			q[++t]=x;
		}
	}
	cout<<f[k&1][n]<<endl;
	int now=n;
	for(int i=k;i>=1;--i){
		cout<<pre[i][now]<<" ";
		now=pre[i][now];
	}
}