questions balancedpara:to check if paranthesis is balanced stringunque:to check is every character in a string is unqiue (O(n)) revstring:to reverse a string twoSum1:to find two numbers that add upto a target number.given a array and a target sum (both of int) twoSum2:twoSum1 but input array is sorted longestsubstring:Given a string s, find the length of the longest substring without repeating characters. anagram:check is two strings are anagrams are not