''' returns the shortest path from a root node to a target node. ''' graph = { 0: [1, 2, 3], 1: [4, 5], 2: [6, 7] } def bfs(g, root, target): q = [[root]] visited = set() while q: path = q.pop(0) vertex = path[-1] if vertex == target: return path elif vertex not in visited: for node in g.get(vertex, []): adj_path = list(path) adj_path.append(node) q.append(adj_path) visited.add(vertex) print(bfs(graph, 0, 6))