156. 트리 순회

백준

1. python

from sys import stdin
from collections import defaultdict

n = int(stdin.readline())

tree = defaultdict(list)

for _ in range(n):
  root, l, r = stdin.readline().strip().split()
  tree[root] = [l, r]

print(tree)

result = [""] * 3 #전위, 중위, 후위

def traverse(node):
  result[0] += node
  if tree[node][0] != ".":
    traverse(tree[node][0]) #왼쪽

  result[1] += node
  if tree[node][1] != ".":
    traverse(tree[node][1]) #오른쪽

  result[2] += node

traverse("A")

for i in result:
  print(i)