# Info & Summary

• Date: 2025-04-19
• Completion Status: A ✅ / B ✅ / C ✅ / D ❌ / E ✅ / F ❌ / G ❌
• Problem Type:

Problem	Type(s)	Data Structure / Algo	🔥 Key Insight / Mark
D	Efficient Counting	Math	⭐
E	Expected Value Optimization	DP/Bottom-Up DP/DFS	🔥🧠
F	Path Enumeration	Meet-in-the-Middle/Bitmask	🔥🛠️

📌 Description

The Meet-in-the-Middle (MITM) technique is a problem-solving strategy commonly used to reduce the time complexity of brute-force solutions by dividing a problem into two smaller subproblems. It is particularly useful when the size of the problem is too large to solve directly using brute force, but splitting it into two halves can make it computationally feasible:

# Info & Summary

• Date: 2025-03-08
• Completion Status: A ✅ / B ✅ / C ✅ / D ✅ / E ❌ / F ❌ / G ❌
• Problem Type:

Problem	Type(s)	Data Structure / Algo	🔥 Key Insight / Mark
D	XOR operation	DFS	⭐
E	XOR operation	BFS/DFS	🔥🧠
F	Inversion number	Fenwick Tree	🔥🛠️🌀
G	Meet-in-the-Middle	Meet-in-the-Middle/Bitmask	🔥🛠️🌀