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1.概念

頂点と同じレベルのノード(兄弟ノード)を最初に参照する方法


->Pythonが提供するディレクトリとリストの資料構造を利用してグラフを表現できます.

コード#コード#

グラフィックの作成

graph = dict()

graph['A'] = ['B', 'C']
graph['B'] = ['A', 'D']
graph['C'] = ['A', 'G', 'H', 'I']
graph['D'] = ['B', 'E', 'F']
graph['E'] = ['D']
graph['F'] = ['D']
graph['G'] = ['C']
graph['H'] = ['C']
graph['I'] = ['C', 'J']
graph['J'] = ['I']

アルゴリズム実装

def bfs(graph, start_node):
    visited = list()
    need_visit = list()
    
    need_visit.append(start_node)
    
    while need_visit:
        node = need_visit.pop(0)
        if node not in visited:
            visited.append(node)
            need_visit.extend(graph[node])
    
    return visited