Problems to solve for better understanding of concepts on Arrays
1. Two Sum ✅
2. Roman to Integer
3. Palindrome Number ✅
4. Maximum Subarray ✅
5. Remove Element ✅
6. Contains Duplicate ✅
7. Add Two Numbers
8. Majority Element✅
9. Remove Duplicates from Sorted Array ✅
10. Valid Anagram ✅
11. Group Anagrams ✅
Beginner Questions once have a look:
1. Two Sum
2. Roman to Integer
3. Palindrome Number
4. Maximum Subarray
5. Remove Element
6. Contains Duplicate
7. Add Two Numbers
8. Majority Element
9. Remove Duplicates from Sorted Array
10. Valid Anagram
11. Group Anagrams
12. Practice them in a row for better understanding and please comment the question you
needed to add in the beginners list
List of Problems topic wise
Finally, here is a list of problems that I solved topic wise and wasn't able to solve them in the first
chance. I used solutions / discuss to check the approach of solving problems. Few are some which
are worth revisiting. Finally, I have solved around 137 problems, so that should suffice for a beginner
to onboard with the process of leetcode grind.
*Click on the topic to save the list
Two Pointers
1. #75 Sort Colors
2. #80 Remove Duplicates from Sorted Array II
3. #88 Merge Sorted Array
4. #457 Circular Array Loop
5. #713 Subarray Product Less Than K
6. #845 Longest Mountain in Array
7. #904 Fruit into baskets
8. #925 Long Pressed name
9. #986 Interval list intersections
Binary Search
1. #33 Search in rotated sorted array
2. #69 Sqrt(x)
3. #153 Find min in rotated sorted array
4. #349 Intersection of two arrays
5. #441 Arranging coins
6. #475 Heaters
7. #658 Find K closest elements
8. #911 Online Election
Hashmap
1. #463 Island Perimeter
2. #535 Encode and decode TinyURL
3. #575 Distribute Candies
4. #739 Daily Temperatures
5. #748 Shortest Completing Word
6. #811 Subdomain visit count
7. #884 Uncommon words from Twos sentences
8. #953 Verifying an Alien Dictionary
9. #961 N-Repeated Element in Size 2N Array
10. #1160 Find words that can be formed by characters
11. #1078 Occurences after bigram
Stack
1. #496 Next Greater Element I
2. #682 Baseball Game
3. #856 Score of Parentheses
4. #946 Validate Stack Sequences
5. #1190 Reverse Substrings Between Each Pair of Parentheses
6. #1209 Remove All Adjacent Duplicates in String II
String
1. #468 Validate IP Address
2. #522 Longest Uncommon Subsequence II
3. #539 Minimum Time Difference
4. #553 Optimal Division
5. #791 Custom Sort String
6. #833 Find and replace in String
7. #835 Image Overlap
8. #893 Groups of Special-Equivalent Strings
9. #1156 Swap For Longest Repeated Character Substring
Sliding Window
1. #424 Longest Repeating Character Replacement
2. #1040 Moving Stones Until Consecutive II
Tree
1. #101 Symmetric Tree
2. #108 Convert Sorted Array to Binary Search Tree
3. #226 Invert Binary Tree
4. #538 Convert BST to Greater Tree
5. #543 Diameter of a Binary Tree
6. #637 Average of Levels in Binary Tree
7. #654 Maximum Binary Tree
8. #669 Trim a Binary Search Tree
9. #589 N-ary Tree Preorder Traversal
10. #894 All Possible Full Binary Trees
11. #979 Distribute Coins in Binary Tree
12. #993 Cousins in a Binary Tree
13. #1022 Sum of Root To Leaf Binary Numbers
14. #1104 Path In Zigzag Labelled Binary Tree
15. #1110 Delete Nodes And Return Forest
I haven't started solving problems from graphs and other intermediate topics, so I don't have them
now, but once I have archive of some good problems, I would certainly share with the leetcode
community.
Here are the clickable links for the competitive programming resources for Java:
1. Coding Platforms
Codeforces: https://codeforces.com/
LeetCode: https://leetcode.com/
HackerRank: https://www.hackerrank.com/domains/tutorials/10-days-of-java
CodeChef: https://www.codechef.com/
AtCoder: https://atcoder.jp/
2. Learning Java for CP
GeeksforGeeks - Java for Competitive Programming:
https://www.geeksforgeeks.org/competitive-programming-in-java/
Java Algorithms on LeetCode: https://leetcode.com/tag/algorithm/?language=java
CP Algorithms: https://cp-algorithms.com/
3. YouTube Channels
Errichto: https://www.youtube.com/channel/UCBr_Fu6q9iHYQCh13jmpbrg
William Lin: https://www.youtube.com/channel/UCKuDLsO0Wwef53qdHPjbU2Q
Pepcoding: https://www.youtube.com/c/Pepcoding
These should be clickable and take you directly to the resources!
