摘要： Ugly Number IIWrite a program to find then-th ugly number.Ugly numbers are positive numbers whose prime factors only include2, 3, 5. For example,1, 2,... 阅读全文

摘要： Add DigitsGiven a non-negative integernum, repeatedly add all its digits until the result has only one digit.For example:Givennum = 38, the process is... 阅读全文

摘要： Binary Tree PathsGiven a binary tree, return all root-to-leaf paths.For example, given the following binary tree: 1 / \2 3 \ 5All root-to-lea... 阅读全文