[알고리즘] DFS, BFS Python 핵심 코드 정리

DFS

# dfs 정의
def dfs(graph, v, visited):
    visited[v] = True
    print(v, end=' ')
    for i in graph[v]:
        if not visited[i]:
            dfs(graph, i, visited)
            
graph = [
    [],
  [2, 3, 8],
  [1, 7],
  [1, 4, 5],
  [3, 5],
  [3, 4],
  [7],
  [2, 6, 8],
  [1, 7]
]

visited = [False] * 9
dfs(graph, 1, visited)

 

BFS

# bfs 정의
from collections import deque

def bfs(graph, v, visited):
    queue = deque([v])
    visited[v] = True
    while queue:
        v = queue.popleft()
        print(v, end=' ')
        for i in graph[v]:
            if not visited[i]:
                queue.append(i)
                visited[i] = True
                
graph = [
  [],
  [2, 3, 8],
  [1, 7],
  [1, 4, 5],
  [3, 5],
  [3, 4],
  [7],
  [2, 6, 8],
  [1, 7]
]

visited = [False] * 9

bfs(graph, 1, visited)