LeetCode--Reverse String Question Write a function that takes a string as input and returns the string reversed. Example: Given s = "hello", return "olleh". Answer class Solution { public: string reverseString(string s) { string str(s.…
A magical string S consists of only '1' and '2' and obeys the following rules: The string S is magical because concatenating the number of contiguous occurrences of characters '1' and '2' generates the string S itself. The first few elements of strin…
Scramble String Given a string s1, we may represent it as a binary tree by partitioning it to two non-empty substrings recursively. Below is one possible representation of s1 = "great": great / \ gr eat / \ / \ g r e at / \ a t To scramble the s…
Given n pairs of parentheses, write a function to generate all combinations of well-formed parentheses. For example, given n = 3, a solution set is: [ "((()))", "(()())", "(())()", "()(())", "()()()" ] …
Given a non-empty string, encode the string such that its encoded length is the shortest. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note: k will be a positive integ…
Given an encoded string, return it's decoded string. The encoding rule is: k[encoded_string], where the encoded_string inside the square brackets is being repeated exactly k times. Note that k is guaranteed to be a positive integer. You may assume th…
Given a non-empty string str and an integer k, rearrange the string such that the same characters are at least distance k from each other. All input strings are given in lowercase letters. If it is not possible to rearrange the string, return an empt…