Hackerrank Problem Solving(Basic) Certificate test soltions Solutions to Certification of Problem Solving Basic on Hackerrank To get a certificate, two problems have to be solved within 90 minutes. The following is a list of possible problems per certificate. Problem Solving (Basic) Active Traders Balanced System Files Partition Longest Subarray Maximum Cost of Laptop Count Nearly Similar Rectangles Parallel Processing Password Decryption Road Repair String Anagram Subarray Sums Unexpected Demand Usernames Changes Vowel Substring