Types: H: int, W: int, N: int, X: List[int], Y: List[int]  
Ranges: 1 ≤ H, W ≤ 2×10^5, 0 ≤ N ≤ 2×10^5, 1 ≤ X[i] ≤ H, 1 ≤ Y[i] ≤ W  
Addtl Info: If i ≠ j, (X[i], Y[i]) ≠ (X[j], Y[j]), (X[i], Y[i]) ≠ (1,1)