https://www.acmicpc.net/problem/1991
시간 제한 : 2초
메모리 제한 : 128MB
class Node:
def __init__(self, data, left_node, right_node):
self.data = data
self.left_node = left_node
self.right_node = right_node
def pre_order(node):
print(node.data, end='')
if node.left_node != '.':
pre_order(tree[node.left_node])
if node.right_node != '.':
pre_order(tree[node.right_node])
def in_order(node):
if node.left_node != '.':
in_order(tree[node.left_node])
print(node.data, end='')
if node.right_node != '.':
in_order(tree[node.right_node])
def post_order(node):
if node.left_node != '.':
post_order(tree[node.left_node])
if node.right_node != '.':
post_order(tree[node.right_node])
print(node.data, end='')
n = int(input())
tree = {}
for i in range(n):
data, left_node, right_node = input().split()
tree[data] = Node(data, left_node, right_node)
pre_order(tree['A'])
print()
in_order(tree['A'])
print()
post_order(tree['A'])