Featured Lists Top 20 Problems on Dynamic programming Top 10 Problems on Backtracking Top 20 Problems on Graph Top 25 Problems on Trees Top 10 Problems on Bits Manipulation Top 15 Problems in LinkedList All Problems # Status Problem video Level Completes Likes 413 ZigZag OR Diagonal traversal in 2d array/Matrix using queue Medium % 0 412 Check if Number is divisible by its digits Beginner % 0 411 Check if the given number is Armstrong number or not Beginner % 0 410 Evaluation of Prefix Expressions (Polish Notation) | Set 1 Medium % 0 409 Minimum Boats Required to rescue people Medium % 0 408 Number of Islands Medium % 1 407 Integer Replacement Problem Medium % 0 406 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 2 Medium % 0 405 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 1 Medium % 0 404 Find all the numbers in the range which has prime set bits. Beginner % 0 403 Check if Graph is Bipartite - Adjacency Matrix using Depth-First Search(DFS) Hard % 0 402 Check if Arithmetic Expression contains duplicate parenthesis Medium % 0 401 Introduction to Bipartite Graphs OR Bigraphs Medium % 0 400 Reverse the Directed Graph Beginner % 0 399 Round Price Problem Hard % 0 398 Smallest Number after Removing K digits Hard % 0 397 Find Third Smallest elements in a given array Beginner % 0 396 Optimizing Test Execution: Managing Test Dependencies for Sequential Order Medium % 0 395 Implement Graph Using Map or dictionary Medium % 0 394 Find the maximum number present in a String Beginner % 0 393 Count number of subgraphs in a given graph Beginner % 0 392 Reverse a Stack using recursion - In Place (Without using extra memory) Hard % 1 391 Check if given an edge is a bridge in the graph Medium % 0 390 Convert Prefix to Postfix Expression Medium % 0 389 Convert Roman Number to Integer Beginner % 0 388 Sort a given stack - Using Temporary Stack Medium % 0 387 Convert Postfix to Prefix Expression Medium % 0 386 Convert Integer to Roman Medium % 0 385 String to Integer (AtoI - ASCII to Integer) - Recursive Solution Medium % 0 384 Grouping of Anagrams Medium % 0 383 Print Processes and its messages from a given log file Medium % 0 382 Linear Search vs Binary Search Beginner % 0 380 Count the number of nodes in a given binary tree Beginner % 0 379 Sieve of Eratosthenes - Find all Prime Numbers less than equal to N | Set 2 Medium % 0 378 Longest contiguous character in a given String - O(N) Solution Beginner % 0 ZigZag OR Diagonal traversal in 2d array/Matrix using queue Check if Number is divisible by its digits Check if the given number is Armstrong number or not Evaluation of Prefix Expressions (Polish Notation) | Set 1 Minimum Boats Required to rescue people Number of Islands Integer Replacement Problem Evaluation of Postfix Expressions (Polish Postfix notation) | Set 2 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 1 Find all the numbers in the range which has prime set bits. Check if Graph is Bipartite - Adjacency Matrix using Depth-First Search(DFS) Check if Arithmetic Expression contains duplicate parenthesis Introduction to Bipartite Graphs OR Bigraphs Reverse the Directed Graph Round Price Problem Smallest Number after Removing K digits Find Third Smallest elements in a given array Optimizing Test Execution: Managing Test Dependencies for Sequential Order Implement Graph Using Map or dictionary Find the maximum number present in a String Count number of subgraphs in a given graph Reverse a Stack using recursion - In Place (Without using extra memory) Check if given an edge is a bridge in the graph Convert Prefix to Postfix Expression Convert Roman Number to Integer Sort a given stack - Using Temporary Stack Convert Postfix to Prefix Expression Convert Integer to Roman String to Integer (AtoI - ASCII to Integer) - Recursive Solution Grouping of Anagrams Print Processes and its messages from a given log file Linear Search vs Binary Search Count the number of nodes in a given binary tree Sieve of Eratosthenes - Find all Prime Numbers less than equal to N | Set 2 Longest contiguous character in a given String - O(N) Solution 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16