mirror of
https://github.com/krahets/hello-algo.git
synced 2024-12-27 00:36:28 +08:00
55 lines
1.3 KiB
Ruby
55 lines
1.3 KiB
Ruby
|
=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
|