Companies

3.Find the Duplicate Number

also at 21 more

3

Medium16 co.

Medium

Arrays Bit Manipulation

also at 15 more

4

4.Valid Paranthesis Checker

Medium50 co.

Medium

Greedy Algorithms

also at 49 more

5

5.Contains Duplicate

Easy15 co.

Easy

Hashing

also at 14 more

6

6.Shortest Distance in a Binary Maze

Medium9 co.

Medium

Graphs

also at 8 more

7

7.3 Sum

Medium42 co.

Medium

also at 41 more

8

8.Reverse Pairs

Hard9 co.

Hard

9.Check for symmetrical BTs

also at 8 more

9

Medium10 co.

Medium

Recursion & Backtracking Binary Trees

also at 9 more

10

10.Implement Min Stack

Medium27 co.

Medium

13.Sort Characters by Frequency

also at 26 more

11

11.Beautiful Arrangement

Medium2 co.

Medium

Recursion & Backtracking

also at 1 more

12

12.Search in a 2D Matrix

Medium18 co.

Medium

Binary Search

also at 17 more

13

Medium15 co.

Medium

Strings Hashing+1

also at 14 more

14

14.Serialize and De-serialize BT

Hard21 co.

Hard

also at 20 more

15

15.Grid unique paths

Medium16 co.

Medium

16.Two Sum II - Input Array Is Sorted

also at 15 more

16

Medium12 co.

Medium

Binary Search

also at 11 more

17

17.Stone Game

Medium3 co.

Medium

also at 2 more

18

18.Partition List

Medium3 co.

Medium

Linked List

also at 2 more

19

19.Delete and Earn

Medium8 co.

Medium

20.Check for balanced binary tree

also at 7 more

20

Medium8 co.

Medium

21.Print all nodes at a distance of K in BT

also at 7 more

21

Medium18 co.

Medium

also at 17 more

22

22.Next Permutation

Medium32 co.

Medium

24.Count Subarrays With Majority Element I

also at 31 more

23

23.Majority Element-II

Medium13 co.

Medium

Hashing

also at 12 more

24

Medium5 co.

Medium

Advanced Range Data Structures

also at 4 more

25

25.House robber

Medium33 co.

Medium

26.How Many Numbers Are Smaller Than the Current Number

also at 32 more

26

Easy2 co.

Easy

Hashing

also at 1 more

27

27.Check if two trees are identical or not

Medium7 co.

Medium

28.Subarrays with K Different Integers

also at 6 more

28

Hard12 co.

Hard

29.Concatenate Non-Zero Digits and Multiply by Sum I

also at 11 more

29

Easy4 co.

Easy

Mathematics

also at 3 more

30

30.Find the Highest Altitude

Easy6 co.

Easy

31.Minimum Cost to Cut a Stick

also at 5 more

31

Hard2 co.

Hard

32.Substring with Concatenation of All Words

also at 1 more

32

Hard6 co.

Hard

Strings

also at 5 more

33

33.Detect a loop in LL

Medium21 co.

Medium

Linked List

also at 20 more

34

34.Maximum Number of Events That Can Be Attended

Medium9 co.

Medium

Heaps

also at 8 more

35

35.Increasing Triplet Subsequence

Medium5 co.

Medium

also at 4 more

36

36.Permutations

Medium14 co.

Medium

Recursion & Backtracking

also at 13 more

37

37.Maximum Rectangles

Hard17 co.

Hard

also at 16 more

38

38.Jump Game II

Medium18 co.

Medium

Greedy Algorithms

also at 17 more

39

39.Set Matrix Zeroes

Medium17 co.

Medium

Arrays Hashing

also at 16 more

40

40.Basic Calculator

Hard13 co.

Hard

42.Final Prices With a Special Discount in a Shop

also at 12 more

41

41.N Queen

Hard19 co.

Hard

Recursion & Backtracking

also at 18 more

42

Easy4 co.

Easy

44.Longest Substring of One Repeating Character

also at 3 more

43

43.Lemonade Change

Medium5 co.

Medium

Greedy Algorithms

also at 4 more

44

Hard4 co.

Hard

Advanced Range Data Structures

also at 3 more

45

45.Meeting Rooms III

Hard6 co.

Hard

Heaps

also at 5 more

46

46.Print the matrix in spiral manner

Medium30 co.

Medium

47.Sliding Window Maximum

also at 29 more

47

Medium36 co.

Medium