o DFS 유형
n, m = map(int, input().split())
graph = []
for i in range(n):
graph.append(list(map(int, input())))
res = 0
dx = [0, 0, -1, 1]
dy = [1, -1, 0, 0]
def dfs(x, y):
if(x <= -1 or x >= n or y <= -1 or y >= m):
return False
ifgraph[x][y] == 0:
graph[x][y] = 1
for i in range(4):
dfs(x+dx[i],y+dy[i])
return True
return False
for i in range(n):
for j in range(m):
if dfs(i, j) == True:
res += 1
print(res)
예제) 4 5
00110
00011
11111
00000
#답3