Prefix Sum
Problems using prefix sum techniques
32 lessons
82 min
Lessons
1. What is Prefix Sum
Pattern overview
2m
2. Prerequisites
What you need first
1m
3. When to Use
Pattern triggers
2m
4. When NOT to Use
Avoid forcing this pattern
2m
5. LeetCode 1480 Running Sum of 1d Array - Problem Statement
The problem
2m1 problems
6. LeetCode 1480 Running Sum of 1d Array - Solution
The core idea
3m
7. LeetCode 1480 Running Sum of 1d Array - Example and Complexity Analysis
Walkthrough and analysis
3m
8. LeetCode 1480 Running Sum of 1d Array - Implementation
The approach
4m1 problems
9. LeetCode 560 Subarray Sum Equals K - Problem Statement
The problem
2m1 problems
10. Quiz: Prefix Sum Relationship
Test your understanding
2m1 problems
11. LeetCode 560 Subarray Sum Equals K - Why Naive Fails
The trap
2m
12. LeetCode 560 Subarray Sum Equals K - Solution
The core idea
3m
13. LeetCode 560 Subarray Sum Equals K - Example and Complexity Analysis
Walkthrough and analysis
3m
14. LeetCode 560 Subarray Sum Equals K - Implementation
The approach
4m1 problems
15. LeetCode 238 Product of Array Except Self - Problem Statement
The problem
2m1 problems
16. Quiz: Product Without Division
Test your understanding
2m1 problems
17. LeetCode 238 Product of Array Except Self - Why Naive Fails
The trap
2m
18. LeetCode 238 Product of Array Except Self - Solution
The core idea
3m
19. LeetCode 238 Product of Array Except Self - Example and Complexity Analysis
Walkthrough and analysis
3m
20. LeetCode 238 Product of Array Except Self - Implementation
The approach
4m1 problems
21. LeetCode 304 Range Sum Query 2D - Immutable - Problem Statement
The problem
2m1 problems
22. LeetCode 304 Range Sum Query 2D - Immutable - Why Naive Fails
The trap
2m
23. LeetCode 304 Range Sum Query 2D - Immutable - Solution
The core idea
3m
24. LeetCode 304 Range Sum Query 2D - Immutable - Example and Complexity Analysis
Walkthrough and analysis
3m
25. LeetCode 304 Range Sum Query 2D - Immutable - Implementation
The approach
4m1 problems
26. LeetCode 523 Continuous Subarray Sum - Problem Statement
The problem
2m1 problems
27. LeetCode 523 Continuous Subarray Sum - Why Naive Fails
The trap
2m
28. LeetCode 523 Continuous Subarray Sum - Solution
The core idea
3m
29. LeetCode 523 Continuous Subarray Sum - Example and Complexity Analysis
Walkthrough and analysis
3m
30. LeetCode 523 Continuous Subarray Sum - Implementation
The approach
4m1 problems
31. Common Mistakes
Common errors to avoid
2m
32. Section Recap
Summary
1m
Practice Problems
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