[백준] 1991번 트리 순회 (파이썬)

1991번: 트리 순회

 

코드

class Node:
    def __init__(self, node, left, right):
        self.node = node
        self.left = left
        self.right = right


def preorder(node):
    print(node.node, end='')
    if node.left != '.':
        preorder(tree[node.left])
    if node.right != '.':
        preorder(tree[node.right])


def inorder(node):
    if node.left != '.':
        inorder(tree[node.left])
    print(node.node,end='')
    if node.right != '.':
        inorder(tree[node.right])

def postorder(node):
    if node.left != '.':
        postorder(tree[node.left])
    if node.right != '.':
        postorder(tree[node.right])
    print(node.node,end='')


if __name__ == '__main__':
    n = int(input())
    tree = dict()

    for _ in range(n):
        node, left, right = map(str, input().split())
        tree[node] = Node(node=node, left=left, right=right)

    preorder(tree['A'])
    print()
    inorder(tree['A'])
    print()
    postorder(tree['A'])