# 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 Max Flow Problem - Ford-Fulkerson Algorithm Hard % 0 10 Convert Infix to Postfix Expression Medium % 0 11 Evaluation of Infix expressions Medium % 0 12 Convert Prefix to Infix Expression Medium % 0 13 Merge K sorted Linked List - Using Priority Queue Hard % 0 14 Valid Brackets – Part 2 | Stack Method Beginner % 0 15 Graph – Find Cycle in Undirected Graph using Disjoint Set (Union-Find) Hard % 0 16 Graph – Count all paths between source and destination Medium % 1 17 Graph – Detect Cycle in a Directed Graph using colors Hard % 0 18 Graph – Detect Cycle in an Undirected Graph using DFS Medium % 0 19 Graph – Detect Cycle in a Directed Graph Medium % 1 20 Separate 0’s and 1’s in a given array Beginner % 0 21 Find the last repeating character in a given string. Beginner % 0 22 Dynamic Programming - Longest Common Subsequence Medium % 0 23 Dynamic Programming - Rod Cutting Problem Medium % 1 24 Dynamic Programming - Maximum size square sub-matrix with all 1s Medium % 1 25 Backtracking - Search a Word In a Matrix Hard % 0 26 Check if one string is Rotation of another string Beginner % 1 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 Graph – Find Cycle in Undirected Graph using Disjoint Set (Union-Find) Graph – Count all paths between source and destination Graph – Detect Cycle in a Directed Graph using colors Graph – Detect Cycle in an Undirected Graph using DFS Graph – Detect Cycle in a Directed Graph Separate 0’s and 1’s in a given array Find the last repeating character in a given string. Dynamic Programming - Longest Common Subsequence Dynamic Programming - Rod Cutting Problem Dynamic Programming - Maximum size square sub-matrix with all 1s Backtracking - Search a Word In a Matrix Check if one string is Rotation of another string 1