bzoj1835[ZJOI2010]基站选址

主席树+决策单调,重写一遍比之前短多了……题解:http://www.cnblogs.com/liu-runda/p/6051422.html

#include<cstdio>
#include<cstring>
#include<vector>
#include<algorithm>
using namespace std;
const int maxn=;
int n;
struct node{
  int sum;node* ch[];
  node(){}
  node(int x){sum=x;ch[]=ch[]=;}
}t[maxn*],*root[maxn];int cnt=;
node* newnode(int x){t[++cnt]=node(x);return t+cnt;}
void Insert(node* rt0,node* &rt,int l,int r,int k,int x){
  rt=new node(rt0->sum+x);
  if(l==r)return;
  int mid=(l+r)>>;
  if(k<=mid){
    Insert(rt0->ch[],rt->ch[],l,mid,k,x);
    rt->ch[]=rt0->ch[];
  }else{
    Insert(rt0->ch[],rt->ch[],mid+,r,k,x);
    rt->ch[]=rt0->ch[];
  }
}
int query(node* rt0,node* rt1,int l,int r,int ql,int qr){
  if(ql>qr)return ;
  if(ql<=l&&r<=qr)return rt1->sum-rt0->sum;
  int mid=(l+r)>>,ans=;
  if(ql<=mid)ans+=query(rt0->ch[],rt1->ch[],l,mid,ql,qr);
  if(qr>mid) ans+=query(rt0->ch[],rt1->ch[],mid+,r,ql,qr);
  return ans;
}
int f[][maxn];
int d[maxn],c[maxn],s[maxn],w[maxn];
struct data{
  int l,r,w;
}range[maxn];
vector<data> D[maxn];
void solve(int j,int l,int r,int L,int R){
  if(l>r)return;
  int mid=(l+r)>>,g=;
  f[j][mid]=0x7fffffff;
  for(int i=L;i<=R&&i<mid;++i){
    int tmp=f[j-][i]+query(root[i],root[mid-],,n,i+,mid-)+c[mid];
    if(tmp<f[j][mid]){
      f[j][mid]=tmp;g=i;
    }
  }
  solve(j,l,mid-,L,g);solve(j,mid+,r,g,R);
}
int main(){
  int k;scanf("%d%d",&n,&k);
  d[]=0x80808080;d[n+]=0x7fffffff;
  for(int i=;i<=n;++i)scanf("%d",&d[i]);
  for(int i=;i<=n;++i)scanf("%d",&c[i]);
  for(int i=;i<=n;++i)scanf("%d",&s[i]);
  for(int i=;i<=n;++i)scanf("%d",&w[i]);
  for(int i=;i<=n;++i){
    range[i].l=lower_bound(d,d+n+,d[i]-s[i])-d;range[i].r=upper_bound(d,d+n+,d[i]+s[i])-d-;
    range[i].w=w[i];
    D[range[i].l].push_back(range[i]);
  }
  root[]=t+;root[]->ch[]=root[]->ch[]=t+;root[]->sum=;
  for(int i=;i<=n;++i){
    root[i]=root[i-];
    for(vector<data>::iterator pt=D[i].begin();pt!=D[i].end();++pt){
      Insert(root[i],root[i],,n,pt->r,pt->w);
    }
  }
  root[n+]=root[n];
  int ans=;for(int i=;i<=n;++i)ans+=w[i];
  for(int i=;i<=n;++i){
    f[][i]=query(root[],root[i-],,n,,i-)+c[i];//printf("...%d\n",f[1][i]);
    ans=min(ans,f[][i]+query(root[i],root[n],,n,i+,n));//printf("%d\n",ans);
  }//printf("%d\n",ans);
  for(int j=;j<=k;++j){
        solve(j,,n,,n);
    for(int i=;i<=n;++i)ans=min(ans,f[j][i]+query(root[i],root[n],,n,i+,n));
  }
  printf("%d\n",ans);
  return ;
}