题目: 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) 题解: 利用循环递归解…

原题链接: http://oj.leetcode.com/problems/restore-ip-addresses/  这道题的解法很接近于NP问题.也是採用递归的解法. 基本思路就是取出一个合法的数字,作为IP地址的一项,然后递归处理剩下的项.能够想象出一颗树,每一个结点有三个可能的分支(由于范围是0-255,所以能够由一位两位或者三位组成).而且这里树的层数不会超过四层,由于IP地址由四段组成,到了之后我们就不是必需再递归下去.能够结束了.这里除了上述的结束条件外,还有一个就是字符串读完了…

Restore IP Addresses My Submissions Question Solution 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.…

题目链接 leetcode 93. Restore IP Addresses 题意 给定一段序列,判断可能组成ip数的所有可能集合 思路 可以采用模拟或者DFS的想法,把总的ip数分成四段,每段判断是否满足题意 class Solution { public: vector<string> ans; vector<string> restoreIpAddresses(string s){ if(!s.size()) return ans; solve(0,0,s,"&qu…

Restore IP Addresses 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 mat…

Restore IP Addresses 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 mat…

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backtracking and invariant during generating the parathese righjt > left  (open bracket and cloase barckst) class Solution { //["((()))","(()())","(())()","()(())","()()()","())(()"] wrong cas…

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题目: 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) 链接: http://l…