uva352 The Seasonal War-python

MAXN = 26
dirs = [[1, 0], [0, 1], [-1, 0], [0, -1], [1, 1], [1, -1], [-1, 1], [-1, -1]]
cnt = 0

def dfs(x, y, m, n):
flag[x][y] = 1
for d in dirs:
nx = x + d[0]
ny = y + d[1]
if 0 <= nx < m and 0 <= ny < n and pic[nx][ny] == '1' and flag[nx][ny] == 0:
dfs(nx, ny, m, n)
while True:
nn = raw_input()
if not nn.isdigit():
break
n = int(nn)
flag = [[0 for col in range(MAXN)] for row in range(MAXN)]
pic = []
ans = 0
cnt += 1
for i in range(n):
pic.append(raw_input())

for i in range(n):
for j in range(n):
if pic[i][j] == '1' and flag[i][j] == 0:
dfs(i, j, n, n)
ans += 1
print("Image number "+str(cnt)+" contains "+str(ans)+" war eagles.")