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不舔题解(然而被prey安利了子树修改用dfs序,,,码的树链剖分才是亲生的树链剖分(豪情壮志脸

明明“树链剖分”四个字那么长维萨不用缩写呢——因为并不卵知缩写到底是树剖还是链剖啊啊啊

  uoj128/bzoj4196

  1 #include<stdio.h>
  2 #include<algorithm>
  3 using namespace std;
  4 
  5 #define maxn 100005
  6 struct node{
  7     int sum,l,r,cover;
  8 }tree[maxn<<2];
  9 int  cnt,v[maxn],next[maxn],first[maxn];
 10 int nn,size[maxn],son[maxn],dep[maxn],in[maxn],out[maxn],fa[maxn],top[maxn];
 11 void add(int st,int end){
 12     v[++cnt]=end;
 13     next[cnt]=first[st];
 14     first[st]=cnt;
 15 }
 16 void dfs(int sss){
 17     size[sss]=1;
 18     son[sss]=-1;
 19     for(int e=first[sss];e;e=next[e]){
 20         dep[v[e]]=dep[sss]+1;
 21         dfs(v[e]);
 22         if(son[sss]==-1||size[v[e]]>size[son[sss]])son[sss]=v[e];
 23         size[sss]+=size[v[e]];
 24     }
 25 }
 26 void build(int sss,int anc){
 27     in[sss]=++nn;top[sss]=anc;
 28     if(son[sss]!=-1)build(son[sss],anc);
 29     for(int e=first[sss];e;e=next[e])
 30         if(v[e]!=son[sss])build(v[e],v[e]);
 31     out[sss]=nn;
 32 }
 33 void haha(int rt,int l,int r){
 34     tree[rt].cover=-1;
 35     tree[rt].l=l;
 36     tree[rt].r=r;
 37     if(l==r)return;
 38     int mid=(l+r)>>1;
 39     haha(rt<<1,l,mid);
 40     haha(rt<<1|1,mid+1,r);
 41 }
 42 int len(int rt){
 43     return tree[rt].r-tree[rt].l+1;
 44 }
 45 void push_down(int rt){
 46     if(tree[rt].cover!=-1){
 47         tree[rt<<1].sum=tree[rt].cover*len(rt<<1);
 48         tree[rt<<1|1].sum=tree[rt].cover*len(rt<<1|1);
 49         tree[rt<<1].cover=tree[rt<<1|1].cover=tree[rt].cover;
 50         tree[rt].cover=-1;
 51     }
 52 }
 53 int query(int rt,int ql,int qr){
 54     if(ql<=tree[rt].l&&qr>=tree[rt].r)return tree[rt].sum;
 55     int ans=0,mid=(tree[rt].l+tree[rt].r)>>1;
 56     push_down(rt);
 57     if(ql<=mid)ans+=query(rt<<1,ql,qr);
 58     if(qr>mid)ans+=query(rt<<1|1,ql,qr);
 59     tree[rt].sum=tree[rt<<1].sum+tree[rt<<1|1].sum;
 60     return ans;
 61 }
 62 void update(int rt,int ql,int qr,int x){
 63     if(ql<=tree[rt].l&&qr>=tree[rt].r){
 64         tree[rt].sum=x*len(rt);
 65         tree[rt].cover=x;
 66         return;
 67     }
 68     push_down(rt);
 69     int mid=(tree[rt].l+tree[rt].r)>>1;
 70     if(ql<=mid)update(rt<<1,ql,qr,x);
 71     if(qr>mid)update(rt<<1|1,ql,qr,x);
 72     tree[rt].sum=tree[rt<<1].sum+tree[rt<<1|1].sum;
 73 }
 74 int install(int vb){
 75     int ans=0,va=0,f1=top[va],f2=top[vb];
 76     while(f1!=f2){
 77         if(dep[f1]<dep[f2])swap(f1,f2),swap(va,vb);
 78         ans+=(in[va]-in[f1]+1)-query(1,in[f1],in[va]);
 79         update(1,in[f1],in[va],1);
 80         va=fa[f1];f1=top[va];
 81     }
 82     if(dep[va]<dep[vb])swap(va,vb);
 83     ans+=(in[va]-in[vb]+1)-query(1,in[vb],in[va]);
 84     update(1,in[vb],in[va],1);
 85     return ans;
 86 }
 87 int uninstall(int x){
 88     int ans=query(1,in[x],out[x]);
 89     update(1,in[x],out[x],0);
 90     return ans;
 91 }
 92 int main(){
 93     freopen("1.in","r",stdin);
 94     int n,m,x;
 95     scanf("%d",&n);
 96     for(int i=1;i<n;i++){
 97         scanf("%d",&fa[i]);
 98         add(fa[i],i);
 99     }
100     dfs(0);build(0,0);
101     scanf("%d",&m);
102     haha(1,1,nn);
103     for(int i=1;i<=m;i++){
104         char op[15];
105         scanf("%s%d",op,&x);  
106         if(op[0]=='i')printf("%d
",install(x));
107         else printf("%d
",uninstall(x));
108     }
109     return 0;
110 }
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原文地址:https://www.cnblogs.com/Ngshily/p/4981289.html