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Great! Here’s a personalized, step-by-step LeetCode learning plan tailored for your Java background—optimized for Salesforce-style interviews and aimed at building depth one problem at a time.

🚀 6-Week LeetCode Mastery Plan (Java Focus)

Goal: Master 35–40 high-impact LeetCode questions with solid solutions, edge cases, and Java coding patterns.

📅 Week 1 — Arrays & Hashing Fundamentals

Day	Problem	Difficulty	Notes
1	Two Sum	Easy	Warm-up, basics of HashMap
2	K-diff Pairs in an Array	Medium	Asked at Salesforce
3	Product of Array Except Self	Medium	Tricky, use prefix products
4	Subarray Sum Equals K	Medium	Prefix sum technique
5	Longest Consecutive Sequence	Medium	Uses HashSet
6–7	Deep dive + review all	—	Recode from memory, test edge cases

📅 Week 2 — Strings & Sliding Window

Day	Problem	Difficulty	Notes
1	Longest Substring Without Repeating Characters	Medium	Classic sliding window
2	Find All Anagrams in a String	Medium	Two pointer logic
3	Maximum Number of Occurrences of a Substring	Medium	Salesforce favorite
4	Palindromic Substrings	Medium	Count using expand-around-center
5	Longest Palindromic Substring	Medium	Dynamic Programming intro
6–7	Code review + discuss in mock Q&A format	—	Try to optimize further

📅 Week 3 — LinkedList & Stack

Day	Problem	Difficulty	Notes
1	Reverse Linked List	Easy	Recursive + Iterative
2	Palindrome Linked List	Easy/Medium	Fast/slow pointer technique
3	Min Stack	Easy	Track min in constant time
4	Valid Parentheses	Easy	Stack problem
5	Daily Temperatures	Medium	Monotonic stack
6–7	Refactor best practices with Java Collections	—	Use Deque, LinkedList, etc.

📅 Week 4 — Trees & Graphs

Day	Problem	Difficulty	Notes
1	Number of Islands	Medium	FAANG + Salesforce classic
2	Clone Graph	Medium	Use BFS/DFS with HashMap
3	Binary Tree Level Order Traversal	Medium	BFS with queue
4	Lowest Common Ancestor of a Binary Tree	Medium	Recursive exploration
5	Word Ladder	Hard	BFS on word graph
6–7	Implement using adjacency lists / Java deque	—	Bonus: practice for follow-ups

📅 Week 5 — Dynamic Programming (DP)

Day	Problem	Difficulty	Notes
1	House Robber	Medium	Try bottom-up and memoization
2	Longest Increasing Subsequence	Medium	Asked at many top firms
3	Coin Change	Medium	Classic DP bottom-up
4	Word Break	Medium	Use DP + dictionary
5	Edit Distance	Hard	Matrix dp with string compare
6–7	Revise, solve time+space optimized version	—	Present code aloud

📅 Week 6 — System Design / High-level + Misc.

Day	Problem	Difficulty	Notes
1	LRU Cache	Medium	Uses LinkedHashMap or custom DoublyList + HashMap
2	LFU Cache	Hard	Salesforce favorite
3	Insert Delete GetRandom O(1)	Medium	HashMap + ArrayList
4	Design Twitter	Medium	Object-oriented design
5	Merge Intervals	Medium	Sorting + merging logic
6–7	Full mock interview round	—	Practice coding + talking through Java APIs

🔧 Tips for Java Code Success

Use List<Integer>, Map<Character, Integer>, and Deque<T> frequently.
Know when to use Collections.sort, Arrays.fill, and Java 8 Streams.
In interviews, focus on:
- Time and space complexity
- Edge cases (null, empty, duplicates)
- Tradeoffs in implementation (e.g., HashMap over TreeMap)

Let me know if you’d like this plan as a printable PDF or if you’d like daily reminders or Java boilerplate code templates.