Java for LeetCode 093 Restore IP Addresses

標籤：

Given a string containing only digits, restore it by returning all possible valid IP address combinations.

For example:
Given "25525511135",

return ["255.255.11.135", "255.255.111.35"]. (Order does not matter)

解題思路：

使用迴圈即可解決，JAVA實現如下：

static public List<String> restoreIpAddresses(String s) {List<String> list = new ArrayList<String>();for (int i = 0; i < 3; i++)for (int j = i + 2; j < i + 5&&j<=s.length()-2; j++)for (int k = j + 1; k < j + 4&&k<=s.length()-1; k++){if (isValid(s.substring(0, i + 1))&& isValid(s.substring(i + 1, j))&& isValid(s.substring(j, k))&& isValid(s.substring(k, s.length())))list.add(s.substring(0, i + 1) + "."+ s.substring(i + 1, j) + "."+ s.substring(j, k) + "."+ s.substring(k, s.length()));}return list;}public static boolean isValid(String s) {if (s.length()>3)return false;int num = Integer.parseInt(s);return num <= 255 && (num + "").equals(s);}

 

Java for LeetCode 093 Restore IP Addresses