2012 2012 ACM/ICPC Asia Regional Jinhua Online Family Name List

http://acm.hdu.edu.cn/showproblem.php?pid=4409

思路：建树后，就是裸LCA了，代码写得不好~~~

#include<stdio.h>
#include<string.h>
#include<string>
#include<vector>
#include<iostream>
#include<algorithm>
#include<map>
using namespace std;
const int maxn = 30003;
int fa[maxn],pre[maxn];
map<string,int>ds;
vector<int>as[maxn];
vector<int>qes[maxn];
vector<int>idd[maxn];
char cs[maxn][100];
int tmp[maxn];
int n,m,cnt;
int ans[maxn],vis[maxn];
struct nd
{
    char op;
    int a,b;
}ask[maxn];
int f[maxn],anc[maxn];
int fin(int x){if(x!=f[x])f[x]=fin(f[x]);return f[x];}
bool cmp(int a,int b)
{
    return strcmp(cs[a],cs[b])<0;
}
void Sort(int x)
{
    int i,j;
    for(i = 0; i < as[x].size(); ++ i)
        Sort(as[x][i]);
    if(i>1){
        for(i = 0; i < as[x].size(); ++ i)
            tmp[i]=as[x][i];
        sort(tmp,tmp+i,cmp);
        for(j = 0; j < i; ++ j)
            as[x][j]=tmp[j];
    }
}
void DFS(int x)
{
    int i;
    puts(cs[x]);
    for(i = 0; i < as[x].size(); ++ i)
    {
        DFS(as[x][i]);
    }
}
void LCA(int u)
{
    int i,v;
    anc[u]=u;
    for(i = 0; i < as[u].size(); ++ i){
        v = as[u][i];
        LCA(v);
        int x = fin(u);
        int y = fin(v);
        if(x^y)f[x]=y;
        anc[fin(u)] = u;
    }
    vis[u]=1;
    for(i = 0; i < qes[u].size(); ++ i)
        if(vis[qes[u][i]]){
            ans[idd[u][i]]=anc[fin(qes[u][i])];
        }
}
void readin()
{
    char s[100],ss[100];
    int i,k,j;
    for(i=0; i <= n; ++ i)
    {as[i].clear();qes[i].clear();idd[i].clear();}
    cnt = 0;
    ds.clear();
    for(i = 0; i < n; ++ i){
        scanf("%s",s);
        for(j = 0; s[j]=='.'; ++ j);
        strcpy(cs[cnt],s);
        ds[string(s+j)] = cnt;
        fa[cnt] = j?pre[j-1]:0;
        if(cnt)as[fa[cnt]].push_back(cnt);
        pre[j] = cnt++;
    }
    Sort(0);

    scanf("%d",&m);
    for(i = 0; i < m; ++ i){
        scanf("%s",s);
        ask[i].op = s[0];
        if(s[0]=='L')continue;
        if(s[0]=='b'){
            scanf("%s",ss);
            ask[i].a = ds[ss];
        }
        if(s[0]=='c'){
            scanf("%s%s",s,ss);
            int a = ds[s];
            int b = ds[ss];
            ask[i].a = a;
            ask[i].b = b;
            qes[a].push_back(b);
            qes[b].push_back(a);
            idd[a].push_back(i);
            idd[b].push_back(i);
        }
    }
    for(i = 0; i <= n; ++ i)f[i]=i;
    memset(vis,0,sizeof(vis));
    LCA(0);
}

void processing()
{
    int i,j,k;
    char s[100];
    for(i = 0; i < m; ++ i)
    {
        if(ask[i].op=='L')DFS(0);
        if(ask[i].op=='b'){
            k = ask[i].a;
            printf("%d\n",as[fa[k]].size());
        }
        if(ask[i].op=='c'){
            k = ans[i];
            if(k==ask[i].a || k==ask[i].b) k = fa[k];
            strcpy(s,cs[k]);
            for(j = 0; s[j]=='.'; ++ j);
            puts(s+j);
        }
    }
}

int main()
{
    while(scanf("%d",&n)==1)
    {
        if(!n)break;
        readin();
    //    puts("IN");
        processing();
    }
    return 0;
}