# Status Problem Level Completes Likes 1 Lexicographically next permutation With One swap Medium % 1 2 Find the number of distinct Islands OR connected components. Hard % 0 3 Check if Graph is Bipartite - Adjacency List using Depth-First Search(DFS) Hard % 0 4 Evaluation of Prefix Expressions (Polish Notation) | Set 2 Medium % 0 5 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Medium % 0 6 Convert Prefix to Postfix Expression Medium % 0 7 Convert Postfix to Prefix Expression Medium % 0 8 Convert Postfix to Infix Expression Medium % 0 9 Convert Infix to Prefix Expression Medium % 0 10 Max Flow Problem - Ford-Fulkerson Algorithm Hard % 0 11 Convert Infix to Postfix Expression Medium % 0 12 Evaluation of Infix expressions Medium % 0 13 Convert Prefix to Infix Expression Medium % 0 14 Merge K sorted Linked List - Using Priority Queue Hard % 0 15 Valid Brackets – Part 2 | Stack Method Beginner % 0 16 Sum of all sub arrays in O(n) Time Hard % 0 17 Dynamic Programming - Egg Dropping Problem Hard % 0 18 Swap two numbers without using extra variable Beginner % 0 19 Stock Single Sell Problem - O(n) Solution Hard % 2 20 Maximum Subarray OR Largest Sum Contiguous Subarray Problem – Divide and Conquer Hard % 0 21 Dynamic Programming - Count all paths in 2D Matrix with Obstructions in it Medium % 1 22 Dynamic Programming - Maximum Subarray Problem Medium % 0 23 Kadane's Algorithm - Maximum Subarray Problem Medium % 1 24 Single Threaded Binary Tree Complete Implementation Hard % 0 25 Generate Maximum revenue by selling K tickets from N windows Medium % 0 Lexicographically next permutation With One swap 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 Max Flow Problem - Ford-Fulkerson Algorithm Convert Infix to Postfix Expression Evaluation of Infix expressions Convert Prefix to Infix Expression Merge K sorted Linked List - Using Priority Queue Valid Brackets – Part 2 | Stack Method Sum of all sub arrays in O(n) Time Dynamic Programming - Egg Dropping Problem Swap two numbers without using extra variable Stock Single Sell Problem - O(n) Solution Maximum Subarray OR Largest Sum Contiguous Subarray Problem – Divide and Conquer Dynamic Programming - Count all paths in 2D Matrix with Obstructions in it Dynamic Programming - Maximum Subarray Problem Kadane's Algorithm - Maximum Subarray Problem Single Threaded Binary Tree Complete Implementation Generate Maximum revenue by selling K tickets from N windows 1