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# include <bits/stdc++.h>
using namespace std ;
const int N = 30 ;
int n ;
string w [ N ] ;
int l [ N ] , r [ N ] , in [ N ] ;
int isleaf [ N ] ;
/*
题目描述：
给出中缀表达式的语法树 请你将后缀表达式输出 括号体现优先级 操作符不可用括号包含。
思路：
后缀表达式就是把运算符后置的表达式，可以抽象成一棵二叉树，其中的的节点有两种情况：
（ ）
（ ）
只有右儿子的情况就是负数啦~ 测试用例： - -1 6
然后就是找根，这个很简单，统计所有节点的入度，唯一的一个入度是 0 的节点就是根。
再写个简单的递归就可以了。
8
* 8 7
a -1 -1
* 4 1
+ 2 5
b -1 -1
d -1 -1
- -1 6
c -1 -1
输出样例1：
(((a)(b)+)((c)(-(d))*)*)
*/
string dfs ( int u ) {
if ( isleaf [ u ] ) return " ( " + w [ u ] + " ) " ;
if ( l [ u ] = = - 1 & & r [ u ] ! = - 1 ) return " ( " + w [ u ] + dfs ( r [ u ] ) + " ) " ; // 负号
return " ( " + dfs ( l [ u ] ) + dfs ( r [ u ] ) + w [ u ] + " ) " ; // 后缀表达式
}
int main ( ) {
cin > > n ;
for ( int i = 1 ; i < = n ; i + + ) {
cin > > w [ i ] > > l [ i ] > > r [ i ] ;
if ( l [ i ] ! = - 1 ) in [ l [ i ] ] + + ;
if ( r [ i ] ! = - 1 ) in [ r [ i ] ] + + ;
if ( l [ i ] = = - 1 & & r [ i ] = = - 1 ) isleaf [ i ] = 1 ; // 叶子
}
// 找根
int root ;
for ( root = 1 ; root < = n ; root + + )
if ( ! in [ root ] ) break ; // 入度为零的是根
cout < < dfs ( root ) < < endl ;
return 0 ;
}
