LeetCode There are some solutions from LeetCode April challenge 2020 Backspace strings compare Binary tree diameter Group anagrams Last stone weight Min stack Number of islands Perfom String Shifts Search in sorted array May challenge 2020 First bad version Jewels and Stones Ransom note Number Complement Magority element First Unique Character in a String Check if it is a straight line June challenge 2020 Invert binary tree Delete node in linked list Reverse string Two city scheduling Random pick with weight Queue reconstruction by height Coin Change2 Power of two Is Subsequence