Types: N: int, K: int, xi: int, yi: int
Ranges: 2 ≤ K ≤ N ≤ 6,000, 1 ≤ xi, yi ≤ 1,000,000
Addtl Info: xi mod 2 = floor(yi ÷ 2) mod 2 (1 ≤ i ≤ N)