Update 37. Sudoku Solver.md

Author: TBXark

37. Sudoku Solver.md

@@ -107,7 +107,6 @@ class Solution {
         var row = [Set<Character>].init(repeating: Set<Character>(), count: 9)
         var block = [Set<Character>].init(repeating: Set<Character>(), count: 9)
         var points = [(p: (x: Int, y: Int), c: Int)]()
-        var points = [(p: (x: Int, y: Int), c: Int)]()
         for y in 0..<9 {
                 let c = board[y][x]
                 guard c != "." else {