# Status Problem Level Completes Likes 1 Find the number of distinct Islands OR connected components. Hard % 0 2 Check if Graph is Bipartite - Adjacency List using Depth-First Search(DFS) Hard % 0 3 Evaluation of Prefix Expressions (Polish Notation) | Set 2 Medium % 0 4 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Medium % 0 5 Convert Prefix to Postfix Expression Medium % 0 6 Convert Postfix to Prefix Expression Medium % 0 7 Convert Postfix to Infix Expression Medium % 0 8 Convert Infix to Prefix Expression Medium % 0 9 Convert Infix to Postfix Expression Medium % 0 10 Evaluation of Infix expressions Medium % 0 11 Convert Prefix to Infix Expression Medium % 0 12 Find longest Snake sequence in a given matrix Medium % 1 13 Dynamic Programming - Count all paths in 2D Matrix with Obstructions in it Medium % 1 14 Kadane's Algorithm - Maximum Subarray Problem Medium % 1 15 Reverse a Linked List in groups of given size 'K' Medium % 0 16 Dynamic Programming - Maximum Product Cutting Problem. Medium % 1 17 Generate Well Ordered Passwords of a Given Length K Medium % 0 18 All N Length Strings from Given String of Length K Medium % 0 19 Print All N Length Strings from Given Number K Hard % 0 20 Dynamic Programming - Maximum size square sub-matrix with all 1s Medium % 1 21 Dynamic Programming - Longest Increasing Subsequence Medium % 1 22 Backtracking - Search a Word In a Matrix Hard % 0 23 Find the Second Largest Element in an Array Beginner % 1 24 Dynamic Programming - Minimum Coin Change Problem Medium % 1 25 Find the Deepest Left Node in a Binary Tree. Medium % 0 26 Find the Deepest Node in a Binary Tree. Medium % 1 27 Find numbers that are palindrome in the decimal and octal Representations Beginner % 0 28 Find All the Well Ordered Permutations of a Given String. Medium % 0 29 Construct a Special Triangle from a Given Array Beginner % 0 30 Colorful Numbers Hard % 1 31 Goldbach's Conjecture Beginner % 0 32 Print All the Subsets of a Given Set (Power Set) Hard % 1 33 Convert Decimal into Irreducible Fraction Beginner % 0 Find the number of distinct Islands OR connected components. Check if Graph is Bipartite - Adjacency List using Depth-First Search(DFS) Evaluation of Prefix Expressions (Polish Notation) | Set 2 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Convert Prefix to Postfix Expression Convert Postfix to Prefix Expression Convert Postfix to Infix Expression Convert Infix to Prefix Expression Convert Infix to Postfix Expression Evaluation of Infix expressions Convert Prefix to Infix Expression Find longest Snake sequence in a given matrix Dynamic Programming - Count all paths in 2D Matrix with Obstructions in it Kadane's Algorithm - Maximum Subarray Problem Reverse a Linked List in groups of given size 'K' Dynamic Programming - Maximum Product Cutting Problem. Generate Well Ordered Passwords of a Given Length K All N Length Strings from Given String of Length K Print All N Length Strings from Given Number K Dynamic Programming - Maximum size square sub-matrix with all 1s Dynamic Programming - Longest Increasing Subsequence Backtracking - Search a Word In a Matrix Find the Second Largest Element in an Array Dynamic Programming - Minimum Coin Change Problem Find the Deepest Left Node in a Binary Tree. Find the Deepest Node in a Binary Tree. Find numbers that are palindrome in the decimal and octal Representations Find All the Well Ordered Permutations of a Given String. Construct a Special Triangle from a Given Array Colorful Numbers Goldbach's Conjecture Print All the Subsets of a Given Set (Power Set) Convert Decimal into Irreducible Fraction 1