poj 3694 Network

/*哈哈我Tarjan套lca.. 丫输出case啥的没看见...*/
#include<iostream>
#include<cstdio>
#include<cstring>
#define maxn 300010
using namespace std;
int n,m,num,head[maxn],low[maxn],dfn[maxn],topt;
int s[maxn],top,f[maxn],sum,belong[maxn],cnt,cas;
int Num,Head[maxn],fa[maxn],c[maxn],ee[maxn],vis[maxn];
struct node{int v,pre;}e[maxn*2];
struct Node{int v,pre;}E[maxn*2];
void Add(int from,int to)
{
    e[num].v=to;
    e[num].pre=head[from];
    head[from]=num++;
}
void add(int from,int to)
{
    E[Num].v=to;
    E[Num].pre=Head[from];
    Head[from]=Num++;
}
void Tarjan(int x,int fa)
{
    low[x]=dfn[x]=++topt;
    s[++top]=x;f[x]=1;
    for(int i=head[x];i!=-1;i=e[i].pre)
      {
          int v=e[i].v;
          if(i==(fa^1))continue;
          if(dfn[v]==0)
            {
                Tarjan(v,i);low[x]=min(low[x],low[v]);
          }
        else if(f[v])low[x]=min(low[x],dfn[v]);
      }
    if(low[x]==dfn[x])
      {
          sum++;
          while(x!=s[top])
            {
                f[s[top]]=0;belong[s[top]]=sum;top--;
          }
        f[s[top]]=0;belong[s[top]]=sum;top--;
      }
}
void Dfs(int now,int from,int dep,int Ei)
{
    fa[now]=from;c[now]=dep;ee[now]=Ei;
    for(int i=Head[now];i!=-1;i=E[i].pre)
      if(E[i].v!=from)
        Dfs(E[i].v,now,dep+1,i);
}
void LCA(int a,int b)
{
    if(c[a]<c[b])swap(a,b);
    int t=c[a]-c[b];
    for(int i=1;i<=t;i++)
      {
          if(vis[ee[a]]==0)cnt--;
          vis[ee[a]]=1;a=fa[a];
      }
    while(a!=b)
      {
          if(vis[ee[a]]==0)cnt--;
        vis[ee[a]]=1;a=fa[a];
        if(vis[ee[b]]==0)cnt--;
          vis[ee[b]]=1;b=fa[b];
      }
}
int main()
{
    while(1)
      {
          scanf("%d%d",&n,&m);
          if(n==0&&m==0)break;
          memset(head,-1,sizeof(head));
          memset(Head,-1,sizeof(Head));
          memset(low,0,sizeof(low));
          memset(dfn,0,sizeof(dfn));
          memset(f,0,sizeof(f));
          memset(belong,0,sizeof(belong));
          memset(vis,0,sizeof(vis));
          memset(c,0,sizeof(c));
          memset(ee,0,sizeof(ee));
          memset(fa,0,sizeof(fa));
          memset(s,0,sizeof(s));
          Num=num=topt=sum=0;
          int u,v;
          for(int i=1;i<=m;i++)
            {
                scanf("%d%d",&u,&v);
                Add(u,v);Add(v,u);
          }
        for(int i=1;i<=n;i++)
          if(dfn[i]==0)
            Tarjan(i,-1);
        for(int u=1;u<=n;u++)
          for(int i=head[u];i!=-1;i=e[i].pre)
            if(belong[u]!=belong[e[i].v])
              add(belong[u],belong[e[i].v]);
        Dfs(1,1,0,0);cnt=sum-1;
        scanf("%d",&m);
        printf("Case %d:
",++cas);
        for(int i=1;i<=m;i++)
          {
              scanf("%d%d",&u,&v);
              int U=belong[u];
              int V=belong[v];
              if(U==V)
                {
                    printf("%d
",cnt);continue;
              }
            LCA(U,V);
            printf("%d
",cnt);
          }
      }
    return 0;
}