50 popular coding interview problems

Preparing for coding interviews? Competitive programming? Then this course will help you for sure: 50 well-chosen problems to increase your problem-solving skills!

Many algorithms concepts covered: dynamic programming, divide and conquer, memoization, backtracking…

And many data structures used: arrays, hashmaps, sets, trees, stacks…

And also, time and space complexity analysis is provided for every problem!

Problems covered:

1- Find pair that sums up to k

2- First repeating character

3- Remove duplicates

4- Find the duplicate

5- Tree depth first search

6- Maximum subarray

7- Reverse a binary tree

8- Longest substring without repeating characters

9- Reverse a linked list

10- Peak finding

11- Palindrome linked list

12- Longest possible palindrome

13- Get substring index

14- Tree breadth first search

15- Sort a linked list

16- Valid binary search tree

17- Minimum cost path in matrix

18- Balanced binary tree

19- Paths in matrix

20- Tree breadth first search II

21- Product of array except self

22- Jump to last index

23- Graph depth first search

24- Graph breadth first search

25- String subsequences

26- Valid brackets

27- Flatten a binary tree

28- Lowest common ancestor

29- Minimum in rotated sorted array

30- Add two linked lists

31- Ways to climb stairs

32- Subsets that sum up to k

33- Ways to decode

34- Remove node from binary search tree

35- Array permutations

36- Longest common subsequence

37- Longest consecutive sequence

38- Edit distance

39- Count sorted vowel strings

40- Smallest number after removing k digits

41- Merge intervals

42- Insert interval

43- Binary tree max sum

44- 0-1 Knapsack

45- Shortest palindrome

46- Coin change

47- Word search

48- N-queens

49- Word ladder

50- Longest increasing subsequence

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• 4 stars: 92 votes
• 5 stars: 209 votes

Frequently Asked Questions

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