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 436 Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Medium % 0 434 Print boundary of given matrix/2D array. Beginner % 1 433 Depth-First Search (DFS) in 2D Matrix/2D-Array - Iterative Solution Beginner % 0 432 Breadth-First Search (BFS) in 2D Matrix/2D-Array Beginner % 1 430 Longest substring with at most K unique characters Medium % 2 427 Number of Islands using BFS Medium % 0 422 Print Stack in reverse order Beginner % 0 419 Print all subsets of an array with a sum equal to zero Medium % 0 415 Hamming Distance between two given strings Beginner % 0 397 Find Third Smallest elements in a given array Beginner % 0 396 Optimizing Test Execution: Managing Test Dependencies for Sequential Order 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 % 0 386 Convert Integer to Roman Medium % 0 385 String to Integer (AtoI - ASCII to Integer) - Recursive Solution Medium % 0 384 Grouping of Anagrams Medium % 0 380 Count the number of nodes in a given binary tree Beginner % 0 378 Longest contiguous character in a given String - O(N) Solution Beginner % 0 377 Convert Postfix to Infix Expression Medium % 0 373 Longest substring with at most two unique characters Medium % 0 371 Convert Infix to Prefix Expression Medium % 0 368 Max Flow Problem - Ford-Fulkerson Algorithm Hard % 0 367 Sum of all Unique elements in a given array Beginner % 0 365 Convert Infix to Postfix Expression Medium % 0 364 Find three smallest elements in a given array Beginner % 0 363 Evaluation of Infix expressions Medium % 0 362 Stack Java Class - Explained Beginner % 0 359 Merge K sorted Linked List - Using Priority Queue Hard % 0 358 Infix, Postfix and Prefix Notations/Expressions Beginner % 0 353 Reverse a given number Beginner % 1 351 Least Recently Used (LRU) Cache – Using HashMap and Doubly Linked List | Set 1 Hard % 1 350 Find first three largest elements in a given array Beginner % 0 344 Given two strings validate the output string Beginner % 0 Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Print boundary of given matrix/2D array. Depth-First Search (DFS) in 2D Matrix/2D-Array - Iterative Solution Breadth-First Search (BFS) in 2D Matrix/2D-Array Longest substring with at most K unique characters Number of Islands using BFS Print Stack in reverse order Print all subsets of an array with a sum equal to zero Hamming Distance between two given strings Find Third Smallest elements in a given array Optimizing Test Execution: Managing Test Dependencies for Sequential Order 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 Integer to Roman String to Integer (AtoI - ASCII to Integer) - Recursive Solution Grouping of Anagrams Count the number of nodes in a given binary tree Longest contiguous character in a given String - O(N) Solution Convert Postfix to Infix Expression Longest substring with at most two unique characters Convert Infix to Prefix Expression Max Flow Problem - Ford-Fulkerson Algorithm Sum of all Unique elements in a given array Convert Infix to Postfix Expression Find three smallest elements in a given array Evaluation of Infix expressions Stack Java Class - Explained Merge K sorted Linked List - Using Priority Queue Infix, Postfix and Prefix Notations/Expressions Reverse a given number Least Recently Used (LRU) Cache – Using HashMap and Doubly Linked List | Set 1 Find first three largest elements in a given array Given two strings validate the output string 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
