[Codetree] 그래프 탐색 Python

https://www.codetree.ai/missions/2/problems/graph-traversal/introduction

코드트리 | 코딩테스트 준비를 위한 알고리즘 정석

 

import sys

input = sys.stdin.readline

n, m = map(int, input().split(" "))

graph = [[] for _ in range(n+1)]
visited = [0 for _ in range(n+1)]
cnt = 0

for _ in range(m):
    a, b = map(int, input().split(" "))
    graph[a].append(b)
    graph[b].append(a)

def dfs(v):
    visited[v] = 1
    global cnt
    cnt += 1 

    for n in graph[v]: 
        if not visited[n]:
            dfs(n)

dfs(1)
print(cnt-1)