# Status Problem video Level Completes Likes 544 Counting the Largest Number Groups by Digit Sum Medium % 2 529 Duplicate even elements in an array Beginner % 1 525 Find the number of pairs with odd XOR Beginner % 2 517 Count number of pairs in an array with sum = K Medium % 0 516 Count similar words in a given array Beginner % 1 509 Find the Number of Contiguous Parking Areas Medium % 1 498 The largest number can be formed from the given number Beginner % 0 495 Print all nested directories and files in a given directory - Recursion Medium % 0 493 Maximum meetings in one room Medium % 0 488 Check if given sudoku is valid or not Medium % 0 485 Construct the Largest number from the given digits Beginner % 1 478 Efficient Robot Problem - Find Minimum Trips Hard % 0 473 Given an array, count the number of pairs with a given sum. Beginner % 0 471 Two Sum Problem Beginner % 0 470 Find if any two intervals overlap in given intervals Medium % 0 465 Find all subsets of size K from a given number N (1 to N) Medium % 0 463 Combinations with sum K from a given number N with repetition Medium % 0 461 Insert a node in the given sorted linked list. Beginner % 1 460 Construct the largest number from the given array Medium % 0 454 Find all unique combinations of numbers (from 1 to 9 ) with sum to N Medium % 0 452 Activity Selection Problem Medium % 0 451 Find the sum of overlapping elements in two sets Beginner % 0 443 Check the completeness of given binary tree | Set 2 - Using Level Order Traversal Medium % 0 440 Given an array, Print sum of all subsets Beginner % 1 437 Lexicographically previous permutation With One swap Medium % 1 436 Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Medium % 0 431 Check the completeness of given binary tree | Set 1 - Using Node Count Medium % 0 425 Check if the given binary tree is Full or not Beginner % 1 422 Print Stack in reverse order Beginner % 0 417 Maximum number edges to make Acyclic Undirected/Directed Graph Beginner % 0 416 Evaluation of Prefix Expressions (Polish Notation) | Set 2 Medium % 0 413 ZigZag OR Diagonal traversal in 2d array/Matrix using queue Medium % 0 410 Evaluation of Prefix Expressions (Polish Notation) | Set 1 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 Counting the Largest Number Groups by Digit Sum Duplicate even elements in an array Find the number of pairs with odd XOR Count number of pairs in an array with sum = K Count similar words in a given array Find the Number of Contiguous Parking Areas The largest number can be formed from the given number Print all nested directories and files in a given directory - Recursion Maximum meetings in one room Check if given sudoku is valid or not Construct the Largest number from the given digits Efficient Robot Problem - Find Minimum Trips Given an array, count the number of pairs with a given sum. Two Sum Problem Find if any two intervals overlap in given intervals Find all subsets of size K from a given number N (1 to N) Combinations with sum K from a given number N with repetition Insert a node in the given sorted linked list. Construct the largest number from the given array Find all unique combinations of numbers (from 1 to 9 ) with sum to N Activity Selection Problem Find the sum of overlapping elements in two sets Check the completeness of given binary tree | Set 2 - Using Level Order Traversal Given an array, Print sum of all subsets Lexicographically previous permutation With One swap Find all unique combinations of exact K numbers (from 1 to 9 ) with sum to N Check the completeness of given binary tree | Set 1 - Using Node Count Check if the given binary tree is Full or not Print Stack in reverse order Maximum number edges to make Acyclic Undirected/Directed Graph Evaluation of Prefix Expressions (Polish Notation) | Set 2 ZigZag OR Diagonal traversal in 2d array/Matrix using queue Evaluation of Prefix Expressions (Polish Notation) | Set 1 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 2 Evaluation of Postfix Expressions (Polish Postfix notation) | Set 1 1 2 3 4