DFS

class Graph:
    def __init__(self, edges, n):  # A list of lists to represent an  adjacency list
        self.adjList = [[] for _ in range(n)]

        # add edges to undirected graph
        for (src, dest) in edges:
            self.adjList[src].append(dest)
            self.adjList[dest].append(src)


# dfs traversing
def recursiveDFS(graph, v, discovered):
    discovered[v] = True
    print(v, end='')

    # do for every edge
    for u in graph.adjList[v]:
        if not discovered[u]:
            recursiveDFS(graph, u, discovered)


if __name__ == '__main__':
    edges = [
        (1, 2), (1, 7), (1, 8), (2, 3), (2, 6), (7, 4), (7, 5), (8, 9)
    ]

n = 12

graph = Graph(edges, n)

discovered = [False] * n

for i in range(n):
    if not discovered[1]:
        recursiveDFS(graph, i, discovered)