[알고리즘] - bfs 구현

def graph():
    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']
    return graph


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


if __name__ == '__main__':
    print(bfs(graph(), 'A'))