Python - DFS Problem solving example

강의 : https://youtu.be/7C9RgOcvkvo

코드 :

# example - DFS problem

# 1. input
n, m = map(int, input().split())

graph = []
for i in range(n):
    graph.append(list(map(int, input()))) # *no space*
    
def dfs(r,c):
    # check out of boundary
    if r<= -1 or r>n or c<=-1 or c>=m:
        return False:
    # check visited
    if graph[r][c]==0:
        graph[r][c] =1
        # top, left, bottom, right
        dfs(r-1, c)
        dfs(r, c-1)
        dfs(r+1, c)
        dfs(r, c+1)
        return True
    return False
    
# 2. check node by DFS
result = 0
for i in range(n):
    for j in range(m):
        if dfs(i,j)==True:
            result += 1
            
# 3. output result
print(result)