参考博客:
https://blog.youkuaiyun.com/sinat_34550050/article/details/52274141
代码:
#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N =1e4+5;
int n,m,k;
ll S;
ll a[N];
int vis[N];
int tot;
struct node
{
int id;
ll val;
};
vector<ll >huan[N];
int len[N];
ll sum[N];
ll num[N*2];
ll ss[N*2];
int q[N*2];
void solve(int id,ll &maxx)
{
int nn=0;
for(int i=0; i<len[id]; i++)
{
num[++nn]=huan[id][i];
}
for(int i=0; i<len[id]; i++)
{
num[++nn]=huan[id][i];
}
memset(ss,0,sizeof(ss));
for(int i=1; i<=nn; i++)
{
ss[i]=ss[i-1]+num[i];
}
int sz=len[id];
ll Ans=0;
int K=m%sz;
int head,tail;
head=tail=0;
for(int i=1; i<=nn; i++)
{
while(head<tail&&ss[i-1]<ss[q[tail-1]]) tail--;
q[tail++]=i-1;
while(head<tail&&i-q[head]>K) head++;
Ans=max(Ans,ss[i]-ss[q[head]]);
}
if(sum[id]>0) Ans+=(m/sz)*sum[id];
maxx=max(maxx,Ans);
Ans=0;
K=sz;
head=tail=0;
for(int i=1; i<=nn; i++)
{
while(head<tail&&ss[i-1]<ss[q[tail-1]]) tail--;
q[tail++]=i-1;
while(head<tail&&i-q[head]>K) head++;
Ans=max(Ans,ss[i]-ss[q[head]]);
}
if(sum[id]>0)
{
int cnt=m/sz-1;
if(cnt<0) cnt=0;
Ans+=1ll*cnt*sum[id];
}
// cout<<"Ans "<<Ans<<endl;
maxx=max(maxx,Ans);
}
int main()
{
int T;
scanf("%d",&T);
int kk=0;
while(T--)
{
scanf("%d %lld %d %d",&n,&S,&m,&k);
for(int i=0; i<n; i++) scanf("%lld",&a[i]);
memset(vis,0,sizeof(vis));
memset(len,0,sizeof(len));
memset(sum,0,sizeof(sum));
for(int i=1; i<=n; i++) huan[i].clear();
tot=0;
for(int i=0; i<n; i++)
{
if(vis[i]) continue;
ll ss=0;
++tot;
for(int j=i;; j=(j+k)%n)
{
if(vis[j]) break;
vis[j]=1;
huan[tot].push_back(a[j]);
len[tot]++;
sum[tot]+=a[j];
}
}
/*
for(int i=1;i<=tot;i++){
cout<<"*********"<<endl;
for(int j=0;j<huan[i].size();j++) cout<<huan[i][j]<<" ";
cout<<endl;
}
*/
ll maxx=0;
for(int i=1; i<=tot; i++)
{
solve(i,maxx);
}
if(maxx>=S)
{
printf("Case #%d: %d\n",++kk,0);
}
else printf("Case #%d: %lld\n",++kk,S-maxx);
}
return 0;
}
/*
1
5 1000 6 1
1 1 -1 -1 1
*/