**Problem Statement:**
Given the required input arguments, write an efficient algorithm to solve the **Kth Smallest Element in Sorted Matrix** problem. Implement the required logic as specified by standard definitions for this classic algorithmic challenge.
**Hint / Expected Approach:**
Binary search on value range + count elements ≤ mid
**Edge Cases to Consider:**
- (1) k = 1
- (2) k = n²
- (3) Duplicate values in matrix