# Status Problem Level Completes Likes 1 In a number, add digits until it becomes a single digit Beginner % 1 2 Print all nested directories and files in a given directory - Recursion Medium % 0 3 Print all subarrays using recursion Medium % 1 4 Given an array, find all unique subsets with a given sum with allowed repeated digits. Medium % 0 5 Print all steps to convert one string to another string Medium % 0 6 Find all subsets of size K from a given number N (1 to N) Medium % 0 7 Find all possible combinations with sum K from a given number N(1 to N) with the repetition of numbers is allowed Medium % 0 8 Given an array, print all unique subsets with a given sum. Medium % 0 9 Find all unique combinations of numbers (from 1 to 9 ) with sum to N Medium % 0 10 Depth-First Search (DFS) in 2D Matrix/2D-Array - Recursive Solution Beginner % 1 11 Find the number of distinct Islands OR connected components. Hard % 0 12 Given an array, Print sum of all subsets Beginner % 1 13 Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Medium % 0 14 Collatz Conjecture - Maximum Steps takes to transform (1, N) to 1. Medium % 0 15 Number of Islands using BFS Medium % 0 16 Print Stack in reverse order. Beginner % 0 17 Print all subsets of an array with a sum equal to zero Medium % 0 18 Number of Islands Medium % 1 19 Minimum No of operations required to convert a given number to 1 - Integer Replacement Problem. Medium % 0 20 Round Price Problem Hard % 0 21 Reverse a Stack using recursion - In Place (Without using extra memory) Hard % 1 22 Collatz Conjecture - Steps to transform Number to 1 Beginner % 0 23 Reverse a given number – Java Code Beginner % 1 24 Generate all the strings of length n from 0 to k-1. Medium % 0 25 Print Numbers from 1 to N without using loop Beginner % 0 26 Reverse a String using Recursion Beginner % 0 27 Graph – Find Cycle in Undirected Graph using Disjoint Set (Union-Find) Hard % 0 28 Graph – Depth First Search using Recursion Beginner % 1 29 Print all subarrays of a given array Medium % 0 30 Text Justification Problem (OR Word Wrap Problem) Hard % 0 31 Divide and Conquer - Rearrange array elements in special order Medium % 0 32 Find the local minima in a given array Medium % 0 33 Check if array is sorted using recursion Beginner % 0 34 Maximum Subarray OR Largest Sum Contiguous Subarray Problem – Divide and Conquer Hard % 0 35 Maximum difference between two elements where larger element appears after the smaller element Medium % 0 In a number, add digits until it becomes a single digit Print all nested directories and files in a given directory - Recursion Print all subarrays using recursion Given an array, find all unique subsets with a given sum with allowed repeated digits. Print all steps to convert one string to another string Find all subsets of size K from a given number N (1 to N) Find all possible combinations with sum K from a given number N(1 to N) with the repetition of numbers is allowed Given an array, print all unique subsets with a given sum. Find all unique combinations of numbers (from 1 to 9 ) with sum to N Depth-First Search (DFS) in 2D Matrix/2D-Array - Recursive Solution Find the number of distinct Islands OR connected components. Given an array, Print sum of all subsets Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Collatz Conjecture - Maximum Steps takes to transform (1, N) to 1. Number of Islands using BFS Print Stack in reverse order. Print all subsets of an array with a sum equal to zero Number of Islands Minimum No of operations required to convert a given number to 1 - Integer Replacement Problem. Round Price Problem Reverse a Stack using recursion - In Place (Without using extra memory) Collatz Conjecture - Steps to transform Number to 1 Reverse a given number – Java Code Generate all the strings of length n from 0 to k-1. Print Numbers from 1 to N without using loop Reverse a String using Recursion Graph – Find Cycle in Undirected Graph using Disjoint Set (Union-Find) Graph – Depth First Search using Recursion Print all subarrays of a given array Text Justification Problem (OR Word Wrap Problem) Divide and Conquer - Rearrange array elements in special order Find the local minima in a given array Check if array is sorted using recursion Maximum Subarray OR Largest Sum Contiguous Subarray Problem – Divide and Conquer Maximum difference between two elements where larger element appears after the smaller element 1 2 3 4 5