Easy 2 point Medium 4 points Hard 6 points Ninja 10 points

Question Type Level Solve
Write a function that sorts list of strings according to string length and then lexicographically? Array Hard Solve
Write a function to add two single digit numbers without using any operators? Challenge Hard Solve
Write a function to find time duration between two times in minutes? String Hard Solve
Write a function to compute the length of the longest substring of a given string that contains at most two distinct characters? String Hard Solve
Write a function that takes a string and removes all characters except alphabets (A-Z, a-z) and digits (0-9)? String Hard Solve
Write a function to compute the number of prime factors of a number? Number Hard Solve
Write a function to find the next number with the same digits? Number Hard Solve
Write a function that takes two arrays of strings, sorts each array individually in ascending order, and then merges them into a single sorted array? Array Hard Solve
Write a function that takes two arrays of strings and returns the longest string found in either array? Array Hard Solve
Write a function that takes an array of integers and returns the length of the longest subarray with sum equal to zero? Array Hard Solve



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