摘要：
Given a string s consists of upper/lower case alphabets and empty space characters ' ', return the length of last word in the string. If the last word 阅读全文
摘要：
A self dividing number is a number that is divisible by every digit it contains. For example, 128 is a self dividing number because 128 % 1 == 0, 128 阅读全文
摘要：
The n queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return the 阅读全文
摘要：
The n queens puzzle is the problem of placing n queens on an n×n chessboard such that no two queens attack each other. Given an integer n, return all 阅读全文