嗯就如上一篇所說,我們縮完點之後,就成爲了一棵樹,然後每個點權對應它到他的父節點的邊是否狗帶,然後每次LCA在鏈上亂跳的時候維護下清空標記就行了,qlog^2n的果然跑得快,172ms。。。。。。
Problem: 3694 User: BPM136
Memory: 19208K Time: 172MS
Language: G++ Result: Accepted
Source Code
/* ***********************************************
Author :BPM136
Created Time :2016/5/6 22:20:26
File Name :A.cpp
************************************************ */
#include<iostream>
#include<cstdio>
#include<algorithm>
#include<cstdlib>
#include<cmath>
#include<cstring>
#define LL long long
#define get(a,i) a&(1<<(i-1))
#define PAU putchar(32)
#define ENT putchar(10)
#define fo(_i,_a,_b) for(int _i=_a;_i<=_b;_i++)
#define efo(_i,_a) for(int _i=last[_a];_i!=0;_i=e[_i].next)
#define file(x) freopen(#x".in","r",stdin),freopen(#x".out","w",stdout);
#define setlargestack(x) int size=x<<20;char *p=(char*)malloc(size)+size;__asm__("movl %0, %%esp\n" :: "r"(p));
using namespace std;
LL read()
{
LL f=1,d=0;char s=getchar();
while (s<48||s>57){if (s==45) f=-1;s=getchar();}
while (s>=48&&s<=57){d=d*10+s-48;s=getchar();}
return f*d;
}
LL readln()
{
LL f=1,d=0;char s=getchar();
while (s<48||s>57){if (s==45) f=-1;s=getchar();}
while (s>=48&&s<=57){d=d*10+s-48;s=getchar();}
while (s!=10) s=getchar();
return f*d;
}
inline void write(LL x)
{
if(x==0){putchar(48);return;}if(x<0)putchar(45),x=-x;
int len=0,buf[20];while(x)buf[len++]=x%10,x/=10;
for(int i=len-1;i>=0;i--)putchar(buf[i]+48);return;
}
inline void writeln(LL x){write(x);ENT;}
const int N = 100005;
const int M = 200005;
struct edge {
int y,next;
}ee[M*2],e[M*2];
int last1[N],ne1;
int last[N],ne;
#define efo1(i,x) for(int i=last1[x];i!=0;i=ee[i].next)
int low[N],dfn[N],Dfn[N],fa[N],mark[N],f[N];
int sum[N<<2],lz[N<<2];
int siz[N],son[N],top[N],first[N],en[N],fat[N],ft[N],dep[N],nu;
int B[M][2],Lb[N],Le[N],L[N],dl[N],Ln,bn;
int n,m,ans,index;
int find(int x) {
if(f[x]==x) return x;
return f[x]=find(f[x]);
}
int findt(int x) {
if(ft[x]==x) return x;
return ft[x]=findt(ft[x]);
}
void add(int x,int y) {
ee[++ne1].y=y;ee[ne1].next=last1[x];last1[x]=ne1;
}
void add2(int x,int y) {
add(x,y); add(y,x);
}
void addt(int x,int y) {
e[++ne].y=y;e[ne].next=last[x];last[x]=ne;
}
void init() {
memset(mark,0,sizeof(mark));
memset(low,0,sizeof(low));
memset(last1,0,sizeof(last1));
memset(last,0,sizeof(last));
memset(fat,0,sizeof(fat));
memset(dfn,0,sizeof(dfn));
ne=ne1=ans=index=nu=0; Ln=1; bn=0;
fo(i,1,n)f[i]=i;
fo(i,1,m) {
int x=read(),y=read();
add2(x,y);
}
}
void Tarjan(int x) {
Dfn[x]=Dfn[fa[x]]+1;
dfn[x]=low[x]=++index;
efo1(i,x) {
int y=ee[i].y;
if(!dfn[y]) {
fa[y]=x;
Tarjan(y);
low[x]=min(low[x],low[y]);
if(low[y]>dfn[x]) {
mark[y]=1;
ans++;
B[++bn][0]=x,B[bn][1]=y;
}else f[find(x)]=find(y);
}else if(fa[x]!=y) low[x]=min(low[x],dfn[y]);
}
}
int root;
void dfs1(int x,int de) {
dep[x]=de;siz[x]=1;int mx=0,num=-1;
efo(i,x) {
int y=e[i].y;
if(y==fat[x]) continue;
fat[y]=x;
dfs1(y,de+1);
siz[x]+=siz[y];
if(siz[y]>mx) {
mx=siz[y];
num=y;
}
}
son[x]=num;
}
void dfs2(int x,int t) {
first[x]=++nu,top[x]=t;
if(son[x]>0)dfs2(son[x],t); else Le[dl[t]]=nu;
efo(i,x) {
int y=e[i].y;
if(y==fat[x]||y==son[x])continue;
fat[y]=x;
dl[y]=++Ln; Lb[dl[y]]=nu+1;
dfs2(y,y); //w[y]=1;
}
en[x]=nu;
}
#define lch (k<<1)
#define rch (k<<1|1)
void buildsegtree(int k,int l,int r) {
if(l==r) {
if(l!=1)sum[k]=1;else sum[k]=0;
lz[k]=0;
// cerr<<l<<' '<<r<<' '<<sum[k]<<endl;
return ;
}
int mid=(l+r)>>1;
buildsegtree(lch,l,mid); buildsegtree(rch,mid+1,r);
sum[k]=sum[lch]+sum[rch]; lz[k]=0;
// cerr<<l<<' '<<r<<' '<<sum[k]<<' '<<sum[lch]<<' '<<sum[rch]<<endl;
}
/*
void insert(int k,int l,int r,int ll,int rr) {
if(l==ll&&r==rr) {
sum[k]=rr-ll;
lz[k]=1;
return ;
}
int mid=(l+r)>>1;
if(rr<=mid)insert(lch,l,mid,ll,rr);else
if(ll>mid)insert(rch,mid+1,r,ll,rr);else {
insert(lch,l,mid,ll,mid);
insert(rch,mid+1,r,mid+1,rr);
}
pushup(k);
}
*/
void pushdown(int k) {
/*
if(lz[k]==1) {
int mid=(l+r)>>1;
lz[lch]=lz[rch]=1;
sum[lch]=mid-l; sum[rch]=r-mid-1;
}else if(lz[k]==2){
sum[lch]=sum[rch]=0;
lz[lch]=lz[rch]=2;
}
*/
sum[lch]=sum[rch]=0;
lz[lch]=lz[rch]=1;
lz[k]=0;
}
int ret1;
int get_ans(int k,int l,int r,int _l,int _r) {
if(l>r||_l>_r)return 0;
if(l==_l&&r==_r) {
ret1=sum[k];
sum[k]=0; lz[k]=1;
return ret1;
}
if(lz[k])pushdown(k);
int mid=(l+r)>>1;
int ret=0;
if(_r<=mid) ret=get_ans(lch,l,mid,_l,_r); else
if(_l>mid) ret=get_ans(rch,mid+1,r,_l,_r); else {
ret=get_ans(lch,l,mid,_l,mid)+get_ans(rch,mid+1,r,mid+1,_r);
}
// cout<<l<<' '<<r<<' '<<_l<<' '<<_r<<' '<<ret<<endl;
sum[k]=sum[lch]+sum[rch];
return ret;
}
int lca,a,ret;
void LCA(int x,int y) {
while(1) {
if(top[x]==top[y]) {
lca=dep[x]<dep[y]?x:y, a=(x==lca)?y:x, ret=0;
// cout<<"LCAarrive"<<first[lca]<<' '<<first[a]<<endl;
if(lca!=a) ret=get_ans(1,1,nu,first[lca]+1,first[a]);
// cout<<"LCA: "<<lca<<' '<<a<<' '<<first[lca]<<' '<<first[a]<<' '<<ret<<endl;
ans-=ret;
return;
}
if(dep[top[x]]<dep[top[y]]) {
int ret=get_ans(1,1,nu,Lb[dl[top[y]]],first[y]);
ans-=ret;
y=fa[top[y]]; //if(w[y]) w[y]=0,ans--;
} else {
int ret=get_ans(1,1,nu,Lb[dl[top[x]]],first[x]);
ans-=ret;
x=fa[top[x]]; //if(w[x]) w[x]=0,ans--;
}
// cout<<x<<' '<<y<<' '<<top[x]<<' '<<top[y]<<endl;
// cout<<dep[top[x]]<<' '<<dep[top[y]]<<endl;
}
}
void checkt(int x,int pre) {
cout<<pre<<' '<<x<<endl;
efo(i,x) {
int y=e[i].y;
if(y!=pre)
checkt(y,x);
}
}
void work() {
Tarjan(1);
// cerr<<ans<<endl;
// fo(i,1,n) tmp[i]=f[i];
// sort(tmp+1,tmp+n+1);
// int tmpn=0;tmp[0]=-1;
// fo(i,1,n) if(tmp[i]!=tmp[i-1]) tmp[++tmpn]=tmp[i];
fo(i,1,n)ft[i]=i;
fo(i,1,bn) {
int x=findt(B[i][0]),y=findt(B[i][1]);
// cout<<"Bz::"<<B[i][0]<<' '<<B[i][1]<<endl;
if(x!=y) {
x=find(B[i][0]),y=find(B[i][1]);
addt(x,y),addt(y,x),root=x;
// cout<<"B:: "<<x<<' '<<y<<endl;
ft[x]=y;
}
}
// cout<<"Root::"<<root<<endl;
// checkt(root,-1);
// cout<<"finishcheck"<<endl;
dfs1(root,1);
Lb[1]=1; dl[root]=1;
dfs2(root,root);
// cout<<"Liannum:: "<<Ln<<endl;
// cout<<Lb[1]<<' '<<Le[1]<<endl;
// fo(i,1,n) cout<<first[i]<<' ';cout<<endl;
// fo(i,1,n) cout<<en[i]<<' ';cout<<endl;
// fo(i,1,n) cout<<top[i]<<' ';cout<<endl;
buildsegtree(1,1,nu);
// fo(i,1,Ln) insert(1,1,nu,Lb[i],Le[i]);//,cout<<Lb[i]<<' '<<Le[i]<<endl;
int T=read();
while(T--) {
int x=read(),y=read();
x=find(x),y=find(y);
// cout<<x<<' '<<y<<' '<<T<<endl;
if(x!=y)LCA(x,y);
// cout<<"Wan?"<<endl;
writeln(ans);
} ENT;
}
int main() {
int T = 0;
while(scanf("%d%d",&n,&m)!=EOF) {
if(n==0&&m==0) return 0;
printf("Case %d:\n",++T);
init();
work();
}
return 0;
}