You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
1.3 KiB
63 lines
1.3 KiB
=begin
|
|
File: binary_tree_dfs.rb
|
|
Created Time: 2024-04-18
|
|
Author: Xuan Khoa Tu Nguyen (ngxktuzkai2000@gmail.com)
|
|
=end
|
|
|
|
require_relative '../utils/tree_node'
|
|
require_relative '../utils/print_util'
|
|
|
|
### 前序走訪 ###
|
|
def pre_order(root)
|
|
return if root.nil?
|
|
|
|
# 訪問優先順序：根節點 -> 左子樹 -> 右子樹
|
|
$res << root.val
|
|
pre_order(root.left)
|
|
pre_order(root.right)
|
|
end
|
|
|
|
### 中序走訪 ###
|
|
def in_order(root)
|
|
return if root.nil?
|
|
|
|
# 訪問優先順序：左子樹 -> 根節點 -> 右子樹
|
|
in_order(root.left)
|
|
$res << root.val
|
|
in_order(root.right)
|
|
end
|
|
|
|
### 後序走訪 ###
|
|
def post_order(root)
|
|
return if root.nil?
|
|
|
|
# 訪問優先順序：左子樹 -> 右子樹 -> 根節點
|
|
post_order(root.left)
|
|
post_order(root.right)
|
|
$res << root.val
|
|
end
|
|
|
|
### Driver Code ###
|
|
if __FILE__ == $0
|
|
# 初始化二元樹
|
|
# 這裡藉助了一個從陣列直接生成二元樹的函式
|
|
root = arr_to_tree([1, 2, 3, 4, 5, 6, 7])
|
|
puts "\n初始化二元樹\n\n"
|
|
print_tree(root)
|
|
|
|
# 前序走訪
|
|
$res = []
|
|
pre_order(root)
|
|
puts "\n前序走訪的節點列印序列 = #{$res}"
|
|
|
|
# 中序走訪
|
|
$res.clear
|
|
in_order(root)
|
|
puts "\nn中序走訪的節點列印序列 = #{$res}"
|
|
|
|
# 後序走訪
|
|
$res.clear
|
|
post_order(root)
|
|
puts "\nn後序走訪的節點列印序列 = #{$res}"
|
|
end
|