链剖-What you are?-大话西游-校内oj2440

 

This article is made by Jason-Cow.
Welcome to reprint.
But please post the writer's address.

http://www.cnblogs.com/JasonCow/

 

链剖+线段树

所以为什么 2017.4.8 C题爆零了！！！

我的暴力分呢？

大话西游AC code 假装考试30分拿到了T△T

 

  1 #include <algorithm>
  2 #include <iostream>
  3 #include <cstdlib>
  4 #include <cstring>
  5 #include <cstdio>
  6 #include <vector>
  7 #include <queue>
  8 #include <map>
  9 #include <set>
 10 using namespace std;
 11 #define file(x) freopen(x".in","r",stdin),freopen(x".out","w",stdout)
 12 const int maxn=(int)1e5+10,maxm=(int)2e5+10;
 13 struct edge{int v,next;}e[maxm];
 14 struct cuttochain{int fa,dep,size,son,top;}T[maxn];
 15 int head[maxn],cnt,idx,n,Q,dfn[maxn],Rank[maxn],U[maxn],V[maxn];
 16 long long W[maxn];
 17 void add(int u,int v){e[++cnt]=(edge){v,head[u]},head[u]=cnt;}
 18 void Add(int i){scanf("%d%d",&U[i],&V[i]);add(U[i],V[i]),add(V[i],U[i]);}
 19 void dfs1(int u,int fa){
 20   T[u].fa=fa,T[u].dep=T[fa].dep+1,T[u].size=1;
 21   for(int i=head[u];i;i=e[i].next){
 22     if(e[i].v!=fa){
 23       dfs1(e[i].v,u);T[u].size+=T[e[i].v].size;
 24       if(T[u].son==0||T[e[i].v].size>T[T[u].son].size)T[u].son=e[i].v;
 25     }
 26   }
 27 }
 28 void dfs2(int u,int top){
 29   T[u].top=top,dfn[u]=++idx,Rank[dfn[u]]=u;
 30   if(T[u].son)dfs2(T[u].son,top);
 31   for(int i=head[u];i;i=e[i].next){
 32     if(e[i].v!=T[u].fa && e[i].v!=T[u].son)dfs2(e[i].v,e[i].v);
 33   }
 34 }
 35 #define ls (x<<1)
 36 #define rs (x<<1|1)
 37 #define mid ((l+r)>>1)
 38 struct segmenttree{long long max,min,sum;}E[maxn<<2];
 39 void up(int x){
 40   E[x].max = max(E[ls].max,E[rs].max);
 41   E[x].min = min(E[ls].min,E[rs].min);
 42   E[x].sum =     E[ls].sum+E[rs].sum;
 43 }
 44 void build(int x,int l,int r){
 45   if(l==r){E[x].max=E[x].sum=E[x].min=W[Rank[l]];}
 46   else{build(ls,l,mid),build(rs,mid+1,r);up(x);}
 47 }
 48 long long Max(int x,int l,int r,int L,int R){
 49   long long ans=0;
 50   if(L<=l&&r<=R)return E[x].max;
 51   else{
 52     if(R<=mid)ans=Max(ls,l,mid,L,R);
 53     else if(L>mid)ans=Max(rs,mid+1,r,L,R);
 54     else ans=max( Max(ls,l,mid,L,R) , Max(rs,mid+1,r,L,R) );
 55   }
 56   return ans;
 57 }
 58 long long Min(int x,int l,int r,int L,int R){
 59   long long ans=(int)1e8+10;
 60   if(L<=l&&r<=R)return E[x].min;
 61   else{
 62     if(R<=mid)ans=Min(ls,l,mid,L,R);
 63     else if(L>mid)ans=Min(rs,mid+1,r,L,R);
 64     else ans=min( Min(ls,l,mid,L,R) , Min(rs,mid+1,r,L,R) );
 65   }
 66   return ans;
 67 }
 68 long long Sum(int x,int l,int r,int L,int R){
 69   long long ans=0;
 70   if(L<=l&&r<=R)return E[x].sum;
 71   else{
 72     if(R<=mid)ans=Sum(ls,l,mid,L,R);
 73     else if(L>mid)ans=Sum(rs,mid+1,r,L,R);
 74     else ans=Sum(ls,l,mid,L,R) + Sum(rs,mid+1,r,L,R);
 75   }
 76   return ans;
 77 }
 78 void updata(int x,int l,int r,int P,int val){
 79   if(l==r){E[x].max=E[x].sum=E[x].min=val;}
 80   else{
 81     if(P<=mid)updata(ls,l,mid,P,val);
 82     else updata(rs,mid+1,r,P,val);
 83     up(x);
 84   }
 85 }
 86 void update(int x,int val){int id=dfn[x];updata(1,1,n,id,val);}
 87 long long query(int x){
 88   long long MAX1=0,MIN1=(int)1e8+10;
 89   long long MAX2=0,MIN2=(int)1e8+10;
 90   if(T[U[x]].dep>T[V[x]].dep){
 91     MAX1=Max(1,1,n,dfn[U[x]],dfn[U[x]]+T[U[x]].size-1);
 92     MIN1=Min(1,1,n,dfn[U[x]],dfn[U[x]]+T[U[x]].size-1);
 93     int LL=1,LR=dfn[U[x]]-1,RL=dfn[U[x]]+T[U[x]].size,RR=n;
 94     if(LL<=LR){
 95       MAX2=max(MAX2,Max(1,1,n,LL,LR));
 96       MIN2=min(MIN2,Min(1,1,n,LL,LR));
 97     }
 98     if(RL<=RR){
 99       MAX2=max(MAX2,Max(1,1,n,RL,RR));
100       MIN2=min(MIN2,Min(1,1,n,RL,RR));
101     }
102   }
103   else{
104     MAX1=Max(1,1,n,dfn[V[x]],dfn[V[x]]+T[V[x]].size-1);
105     MIN1=Min(1,1,n,dfn[V[x]],dfn[V[x]]+T[V[x]].size-1);
106     int LL=1,LR=dfn[V[x]]-1,RL=dfn[V[x]]+T[V[x]].size,RR=n;
107     if(LL<=LR){
108       MAX2=max(MAX2,Max(1,1,n,LL,LR));
109       MIN2=min(MIN2,Min(1,1,n,LL,LR));
110     }
111     if(RL<=RR){
112       MAX2=max(MAX2,Max(1,1,n,RL,RR));
113       MIN2=min(MIN2,Min(1,1,n,RL,RR));
114     }
115   }
116   //cout<<"MAX1="<<MAX1<<endl;cout<<"MIN1="<<MIN1<<endl;cout<<"MAX2="<<MAX2<<endl;cout<<"MIN2="<<MIN2<<endl;
117   cout<<MAX1*MIN1+MAX2*MIN2<<endl;
118   return 0;
119 }
120 
121 int main(){
122   file("a");
123   scanf("%d%d",&n,&Q);
124   for(int i=1;i<=n;i++)scanf("%lld",&W[i]);
125   for(int i=1;i<n;i++)Add(i);
126   dfs1(1,0),dfs2(1,1),build(1,1,n);
127   for(int i=1;i<=Q;i++){
128     char o[15];scanf("%s",o+1);
129     if(o[1]=='Q'){int x;scanf("%d",&x);query(x);}
130     else{int id;long long val;scanf("%d%lld",&id,&val);update(id,val);}
131   }
132   return 0;
133 }

 

posted @ 2017-04-08 14:46  墨鳌  阅读(254)  评论(0)  编辑  收藏  举报