给定一个只包含数字的字符串，复原它并返回所有可能的 IP 地址格式。
示例:
1
2
|
输入: "25525511135"
输出: ["255.255.11.135", "255.255.111.35"]
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
class (object):
def restoreIpAddresses(self, s):
"""
:type s: str
:rtype: List[str]
"""
def dfs(ans, t, level, s):
if level < 4 and not s:
return
if level > 4 and s:
return
if level == 4 and not s:
ans.add('.'.join(t))
return
for i in range(1, 4):
temp = s[:i]
if temp and int(temp) <= 255:
if len(temp) >= 2 and temp[0] == '0':
continue
t.append(temp)
dfs(ans, t, level+1, s[i:])
t.pop()
ans = set()
dfs(ans, [], 0, s)
return ans
|
近期评论