hello-algo/zh-hant/codes/ruby/chapter_graph/graph_dfs.rb
Yudong Jin 870e3e5cb2
Bug fixes and improvements (#1318)
* Sync zh and zh-hant versions

* Update en/README.md

* Add a Q&A for chapter of introduction

* Update the callout headers

* Sync zh ang zh-hant versions

* Bug fixes
2024-04-30 15:52:05 +08:00

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=begin
File: graph_dfs.rb
Created Time: 2024-04-25
Author: Xuan Khoa Tu Nguyen (ngxktuzkai2000@gmail.com)
=end
require 'set'
require_relative './graph_adjacency_list'
require_relative '../utils/vertex'
### 深度優先走訪輔助函式 ###
def dfs(graph, visited, res, vet)
res << vet # 記錄訪問頂點
visited.add(vet) # 標記該頂點已被訪問
# 走訪該頂點的所有鄰接頂點
for adj_vet in graph.adj_list[vet]
next if visited.include?(adj_vet) # 跳過已被訪問的頂點
# 遞迴訪問鄰接頂點
dfs(graph, visited, res, adj_vet)
end
end
### 深度優先走訪 ###
def graph_dfs(graph, start_vet)
# 使用鄰接表來表示圖,以便獲取指定頂點的所有鄰接頂點
# 頂點走訪序列
res = []
# 雜湊集合,用於記錄已被訪問過的頂點
visited = Set.new
dfs(graph, visited, res, start_vet)
res
end
### Driver Code ###
if __FILE__ == $0
# 初始化無向圖
v = vals_to_vets([0, 1, 2, 3, 4, 5, 6])
edges = [
[v[0], v[1]],
[v[0], v[3]],
[v[1], v[2]],
[v[2], v[5]],
[v[4], v[5]],
[v[5], v[6]],
]
graph = GraphAdjList.new(edges)
puts "\n初始化後,圖為"
graph.__print__
# 深度優先走訪
res = graph_dfs(graph, v[0])
puts "\n深度優先走訪DFS頂點序列為"
p vets_to_vals(res)
end