hdu3974 找上属的模拟

There is a company that has N employees(numbered from 1 to N),every employee in the company has a immediate boss (except for the leader of whole company).If you are the immediate boss of someone,that person is your subordinate, and all his subordinates are your subordinates as well. If you are nobody's boss, then you have no subordinates,the employee who has no immediate boss is the leader of whole company.So it means the N employees form a tree. 

The company usually assigns some tasks to some employees to finish.When a task is assigned to someone,He/She will assigned it to all his/her subordinates.In other words,the person and all his/her subordinates received a task in the same time. Furthermore,whenever a employee received a task,he/she will stop the current task(if he/she has) and start the new one. 

Write a program that will help in figuring out some employee’s current task after the company assign some tasks to some employee.

InputThe first line contains a single positive integer T( T <= 10 ), indicates the number of test cases. 

For each test case: 

The first line contains an integer N (N ≤ 50,000) , which is the number of the employees. 

The following N - 1 lines each contain two integers u and v, which means the employee v is the immediate boss of employee u(1<=u,v<=N). 

The next line contains an integer M (M ≤ 50,000). 

The following M lines each contain a message which is either 

"C x" which means an inquiry for the current task of employee x 

or 

"T x y"which means the company assign task y to employee x. 

(1<=x<=N,0<=y<=10^9)OutputFor each test case, print the test case number (beginning with 1) in the first line and then for every inquiry, output the correspond answer per line.Sample Input

1 
5 
4 3 
3 2 
1 3 
5 2 
5 
C 3 
T 2 1
 C 3 
T 3 2 
C 3

Sample Output

Case #1:
-1 
1 
2

译文：

有一个公司有N个员工（从1到N），公司里的每个员工都有一个直接的老板（除了整个公司的领导），如果你是某人的顶头上司，那个人就是你的下属，他的下属也都是你的下属。如果你不是任何人的老板，那么你就没有下属，没有直接上司的员工是整个公司的领导，这就意味着N员工组成了一棵树。
公司通常会指派一些任务给一些员工完成，当分配给某人的任务时，他/她会把它分配给所有的下属，换句话说，这个人和他/她的下属同时接受一项任务。此外，每当员工收到任务时，他/她将停止当前任务（如果他/她有）并启动新任务。
写，有助于在公司给某个员工分配任务后，计算出员工的当前任务。

 

题解：这道题不知道为什么归类为线段树这一类里面，感觉没什么关系，就是模拟吧，好像就过了，向上找直到最终祖先为止，

然后找时间戳最迟

#include<cstdio>
#include<iostream>
#include<algorithm>
#include<cmath>
#include<cstring>
const int MAXN=50007;
char s[20];
int num,fa[MAXN],zhi[MAXN],now[MAXN],u,v,t,ans,mm,x,y,n,q,fzy=0;
using namespace std;
void query(int x)
{
    if (x==-1) return;
    if (zhi[x]!=-1&&now[x]>mm)
    {
        mm=now[x];
        ans=zhi[x];
    }
    query(fa[x]);
}
int main()
{
    scanf("%d",&t);
    while (t--)
    {
        printf("Case #%d:
",++fzy); 
        memset(fa,-1,sizeof(fa));
        memset(zhi,-1,sizeof(zhi));
        memset(now,-1,sizeof(now));
        num=0;
        scanf("%d",&n);
        for (int i=1,v,u;i<n;i++)
        {
            scanf("%d%d",&v,&u);
            fa[v]=u;
        }
        scanf("%d",&q);
        for (int i=1;i<=q;i++)
        {
            scanf("%s",&s);
            if (s[0]=='C') 
            {
                scanf("%d",&x);
                ans=-1;mm=-10;
                query(x);
                printf("%d
",ans);
            }
            else
            {
                scanf("%d%d",&x,&y);
                zhi[x]=y;
                now[x]=++num;
            }
        }
    }
}

的。