Baekjoon Online Judge 1260번 파이썬

문제 링크
https://www.acmicpc.net/problem/1260

1260번: DFS와 BFS

DFS, BFS 유형을 처음 접해보는 내 입장에서는 정말 어려운 문제였다.
이 문제를 반복해서 풀어봐야 할 것 같다.


정답 코드

import sys
from collections import deque

N, M, V = map(int, sys.stdin.readline().split())

graph = [[0]*(N+1) for i in range(N+1)]
for i in range(M):
    from_n, to_n = map(int, input().split())
    graph[from_n][to_n] = graph[to_n][from_n] = 1
  #양방향이니까

dfs_visited = [False] * (N+1)
def dfs(start_node):
    dfs_visited[start_node] = 1
    print(start_node, end=' ')
    for i in range(1, N + 1):
        if dfs_visited[i] == 0 and graph[start_node][i] == 1:
            dfs(i)

bfs_visited = [False] * (N+1)
def bfs(start_node):
    queue = [start_node]
    bfs_visited[start_node] = 1
    
    while queue:
        start_node = queue.pop(0)
        print(start_node, end=' ')
        for i in range(1, N + 1):
            if bfs_visited[i] == 0 and graph[start_node][i] == 1:
                queue.append(i)
                bfs_visited[i] = 1
        
  
dfs(V)
print()
bfs(V)