Intermediate

Visualized Problem Solving

Data Structures as Pictures

Coding-interview problems solved on screen, in Java. Every problem gets worked examples, a brute force animated beside the line of code that's running, the complete code explained line by line, then the best solution the same way. Each module opens with a long concept episode that teaches the pattern itself.

21 episodes · 2 hours · Java

Start with Episode 2 →

Arrays

11 episodes · 1 h 0 min
  1. 02 Two Sum LeetCode 1 4:47
  2. 03 Contains Duplicate LeetCode 217 4:25
  3. 04 Contains Duplicate II LeetCode 219 5:48
  4. 05 Valid Anagram LeetCode 242 5:13
  5. 06 Group Anagrams LeetCode 49 5:56
  6. 07 Product of Array Except Self LeetCode 238 5:39
  7. 08 Top K Frequent Elements LeetCode 347 5:20
  8. 09 Roman to Integer LeetCode 13 5:46
  9. 10 Verify an Alien Dictionary LeetCode 953 5:38
  10. 11 Longest Consecutive Sequence LeetCode 128 6:05
  11. 12 First Missing Positive LeetCode 41 5:32

Sliding window

10 episodes · 57 min
  1. 14 Maximum Average Subarray I LeetCode 643 6:28
  2. 15 Best Time to Buy and Sell Stock LeetCode 121 5:14
  3. 16 Minimum Size Subarray Sum LeetCode 209 5:44
  4. 17 Longest Substring Without Repeating Characters LeetCode 3 5:31
  5. 18 Max Consecutive Ones III LeetCode 1004 5:36
  6. 19 Fruit Into Baskets LeetCode 904 5:48
  7. 20 Longest Repeating Character Replacement LeetCode 424 6:12
  8. 21 Permutation in String LeetCode 567 4:43
  9. 22 Sliding Window Maximum LeetCode 239 6:00
  10. 23 Minimum Window Substring LeetCode 76 5:48