摘要：
You are given a binary tree in which each node contains an integer value. Find the number of paths that sum to a given value. The path does not need t 阅读全文
摘要：
X city opened a new cinema, many people would like to go to this cinema. The cinema also gives out a poster indicating the movies’ ratings and descrip 阅读全文
摘要：
Given a table salary, such as the one below, that has m=male and f=female values. Swap all f and m values (i.e., change all f values to m and vice ver 阅读全文
摘要：
There is a table World + + + + + + | name | continent | area | population | gdp | + + + + + + | Afghanistan | Asia | 652230 | 25500100 | 20343000 | | 阅读全文