Git hack happens when site maintainers use Git to manage the source code of the website but forget to deleting .git directory. By accessing http://your.target.site/.git/ , you can easily find Git information and even the source code of the target website. Sometimes you may see 403 when you are trying to visit that URL, but that is because the access to directories is restricted. In this case, you can still access and download certain files if you know the exact URL to the file.
Today I spent some time on practicing coding. When I was trying to solve a problem about finding paths with elements whose sum equals to a specified value, given a binary tree and a value, I stumble against some unknown problems.
K sum problems are the sort of problems that asking you to find the k numbers whose sum is the target when given a number array or list. On LeetCode, there are two sum and three sum problems. Today, I am gonna discuss such kind of problems.