记录编号	418737	评测结果	AAAAAA
题目名称	无根树转有根树	最终得分	100
用户昵称	HeHe	是否通过	通过
代码语言	C++	运行时间	0.271 s
提交时间	2017-07-01 10:05:29	内存使用	9.40 MiB

#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
using namespace std;

namespace IO{
	inline char getc(void);
	inline int in(void);
	inline void write(int x);
	inline void write();
	inline void write_all();

	char ops[1 << 18], *opt = ops, *const opt_end = ops + (1 << 18);
	char *p = new char[20]{0};

	inline char getc(void){
		static char buf[1 << 18], *fs, *ft;
		return (fs == ft && (ft = (fs = buf) + fread(buf, 1, 1 << 18, stdin)), fs == ft) ? EOF : *fs++;
	}

	inline int in(void){
		register int res = 0;
		register char tmp = getc();
		while(!isdigit(tmp)) tmp = getc();
		while(isdigit(tmp))
			res = (res + (res << 2) << 1) + (tmp ^ 48),
			tmp = getc();
		return res;
	}

	inline void write(int x){
		if(x < 0){
			*(opt++) = '-';
			if(opt == opt_end) write_all();
			x = -x;
		}
		
		do{
			*(++p) = (x % 10) | 0x30;
			x /= 10;
		}while(x);

		while(*p){
			*(opt++) = *(p--);
			if(opt == opt_end) write_all();
		}

		*(opt++) = ' ';
		if(opt == opt_end) write_all();
		return ;
	}

	inline void write(void){
		*(opt++) = '\n';
		if(opt == opt_end) write_all();
		return ;
	}

	inline void write_all(void){
		fwrite(ops, 1, opt - ops, stdout);
		opt = ops;
		return ;
	}
}
using IO::in;
using IO::write;
using IO::write_all;

const int MAXN = 1e6 + 10;

struct EDGE{
	int to;
	EDGE *ne;
	
	EDGE(){;}
	EDGE(int _to, EDGE *_ne){
		to = _to;
		ne = _ne;
	}
};

inline void add_edge(int fr, int to);
inline void bfs(void);

EDGE *head[MAXN];
int fa[MAXN];
int N, U;

int main(){
#ifndef LOCAL
	freopen("wgs.in", "r", stdin);
	freopen("wgs.out", "w", stdout);
#else
	freopen("test.in", "r", stdin);
#endif
	memset(fa, 0xff, sizeof(fa));
	
	N = in(), U = in();
	for(int i = 1; i < N; ++i) add_edge(in(), in());
	
	bfs();
	N = in();
	for(int i = 0; i < N; ++i) write(fa[in()]);
	
	write_all();
	return 0;
}

inline void add_edge(int fr, int to){
	head[fr] = new EDGE(to, head[fr]);
	head[to] = new EDGE(fr, head[to]);
	return ;
}

inline void bfs(void){
	static queue<int> que;
	static bool vis[MAXN];
	static int u, v;
	
	while(!que.empty()) que.pop();
	memset(vis, 0x00, sizeof(vis));
	
	que.push(U);
	vis[U] = true;
	
	while(!que.empty()){
		u = que.front();
		que.pop();
		for(register EDGE *e = head[u]; e; e = e->ne){
			if(vis[v = e->to]) continue;
			que.push(v);
			vis[v] = true;
			fa[v] = u;
		}
	}
	
	return ;
}