HDU 4409 - Family Name List （LCA）

Family Name List

Time Limit: 2000/1000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 1345    Accepted Submission(s): 443

Problem Description

Kong belongs to a huge family. Recently he got a family name list which lists all men (no women) in his family over many generations. 

The list shows that the whole family has a common ancestor, let's call him Mr. X. Of course, everybody except Mr.X in the list is Mr. X's descendant. Everybody's father is shown in the list except that Mr. X's father is not recorded. We define that Mr. X's generation number is 0. His son's generation number is 1.His grandson's generation number is 2, and so on. In a word, everybody's generation number is 1 smaller than his son's generation number. Everybody's generation number is marked in some way in the list.

Now Kong is willing to pay a lot of money for a program which can re-arrange the list as he requires ,and answer his questions such as how many brothers does a certain man have, etc. Please write this program for him.

 

Input

There are no more than 15 test cases. 
For each test case:
The first line is an integer N( 1 <= N <= 30,000), indicating the number of names in the list.
The second line is the name of Mr. X.
In the next N-1 lines, there is a man's name in each line. And if the man's generation number is K, there are K dots( '.') before his name.

Please note that :
1) A name consists of only letters or digits( '0'-'9').
2) All names are unique.
3) Every line's length is no more than 60 characters.
4) In the list, a man M's father is the closest one above M whose generation number is 1 less than M.
5) For any 2 adjacent lines in the list, if the above line's generation number is G1 and the lower line' s generation number is G2, than G2 <= G1 +1 is guaranteed. 

After the name list, a line containing an integer Q(1<=Q<=30,000) follows, meaning that there are Q queries or operations below.

In the Next Q lines, each line indicates a query or operation. It can be in the following 3 formats:
1) L
Print the family list in the same format as the input, but in a sorted way. The sorted way means that: if A and B are brothers(cousins don’t count), and A's name is alphabetically smaller than B's name, then A must appear earlier than B. 
2) b name
Print out how many brothers does "name" have, including "name" himself.
3) c name1 name2
Print out the closest common ancestor of "name1" and "name2". "Closest" means the generation number is the largest. Since Mr. X has no ancestor in the list, so it's guaranteed that there is no question asking about Mr. X's ancestor. 

The input ends with N = 0.

 

Output

Already mentioned in the input.

 

Sample Input

9Kongs.son1..son1son2..son1son1...sonkson2son1...son1son2son2..son1son3...son1son3son1.son07Lb son1son3son1b son1son2b sonkson2son1b son1c sonkson2son1 son1son2son2c son1son3son1 son1son20

 

Sample Output

Kongs.son0.son1..son1son1...son1son2son2...sonkson2son1..son1son2..son1son3...son1son3son11322son1son1son1

 

Source

2012 ACM/ICPC Asia Regional Jinhua Online 

 

注意不能把自己当祖先。

注意根的兄弟数是1。son[fa[root]]=1;

用string排序和输入和修改会简单

#include <iostream>
#include <stdio.h>
#include <math.h>
#include <string.h>
#include <string>
#include <algorithm>
#include <map>
#include <vector>
using namespace std;
#define LL long long
const int maxn = 40000+12;
int fa[maxn][20],d[maxn];
int son[maxn];
int n;
map<string,int> mp;
string name[maxn];
int on[70];
vector<int> G[maxn];

bool cmd(int a,int b)
{
    return name[a]<name[b];
}

void dfs(int u)
{
    sort(G[u].begin(),G[u].end(),cmd);
    for(int i=0;i<G[u].size();i++){
        int v=G[u][i];
        d[v]=d[u]+1;
        fa[v][0]=u;
        dfs(v);
    }
    son[u]=(int)G[u].size();

}
void lcainit()
{
    for(int I=1;(1<<i)<=n;i++){
        for(int j=1;j<=n;j++){
            fa[j][i]=fa[fa[j][i-1]][i-1];
        }
    }

}

void init()
{
    d[1]=1;
    mp.clear();
    for(int i=0;i<=n;i++)
        G[i].clear();
    memset(fa,0,sizeof fa);
    memset(son,0,sizeof son);
}


void pf(int u,int bei)
{
    for(int i=1;i<=bei;i++) printf(".");
    cout<<name[u]<<endl;
    for(int i=0;i<G[u].size();i++){
        int v=G[u][i];
        pf(v,bei+1);
    }
}


string query(int a,int b)
{
    if(d[a]<d[b]) swap(a, b);
    int dis=d[a]-d[b];
    for(int i=0;(1<<i)<=dis;i++){
        if((1<<i)&dis)
            a=fa[a][i];
    }
    if(a==b) return name[fa[a][0]];
    else{
        for(int i=(int)log2(n);i>=0;i--){
            if(fa[a][i]!=fa[b][i]){
                a=fa[a][i];
                b=fa[b][i];
            }
        }
        a=fa[a][0];
        return name[a];
    }

}
int main()
{
//     ios::sync_with_stdio(false);

    while(~scanf("%d",&n)&&n){
        init();
        for(int i=1;i<=n;i++){
            string nm;
            cin>>nm;
            int len=nm.length();
            int j;
            for(j=0;j<len;j++){
                if(nm[j]!='.')
                    break;
            }
            nm.erase(nm.begin(),nm.begin()+j);
            mp[nm]=i;
            on[j]=i;
            if(i!=1){
                G[on[j-1]].push_back(i);
            }
            name[i]=nm;
        }
        dfs(1);
        lcainit();
        int q;
        scanf("%d",&q);
        while(q--){
            char k;
            cin>>k;
            if(k=='L'){
                pf(1,0);
            }else if(k=='b'){
                string s;cin>>s;
                if(s==name[1]){
                    printf("1\n");
                }else
                    printf("%d\n",son[fa[mp[s]][0]]);
            }else{
                string s1,s2;
                cin>>s1>>s2;
                cout<<query(mp[s1],mp[s2])<<endl;
            }
        }

    }

    return 0;
}