I just took an Amazon online test and I messed it up badly. I am out of practice and have low confidence in writing code.
Are there any coding sites with test harnesses for basic data structures and with basic problems like arrays, strings, linked lists, graph adjacency lists etc, so that I can brush up on basic code like reversing linked list, checking if linked list is palindrome, sorting linked list, finding a substring in a string etc. This would make basic DS brushing fun.
I know there are sites like codechef and topcoder, but from what I have seen, these don't have such basic list, graph conceptual DS questions and test harnesses.