Merge pull request #2408 from krishna1m/0036-valid-sudoku

Create: 0036-valid-sudoku.scala

Author: krishna1m

scala/0036-valid-sudoku.scala

@@ -0,0 +1,32 @@
+object Solution {
+  def isValidSudoku(board: Array[Array[Char]]): Boolean = {
+    import scala.collection.mutable.{Set => MSet}
+    val rowSet = MSet[(Int, Char)]()
+    val colSet = MSet[(Int, Char)]()
+    val squareSet = MSet[(Int, Int, Char)]()
+
+    val indices = for {
+      i <- (0 to 8).toList
+      j <- (0 to 8).toList
+    } yield (i, j)
+
+    indices
+      .map { case (i, j) =>
+        (i, j, board(i)(j))
+      }
+      .filter(_._3 != '.')
+      .forall { case (i, j, char) =>
+        if(
+            rowSet.contains((i, char))
+          | colSet.contains((j, char))
+          | squareSet.contains((i / 3, j / 3, char))
+        ) false
+        else {
+          rowSet += ((i, char))
+          colSet += ((j, char))
+          squareSet += ((i / 3, j / 3, char))
+          true
+        }
+      }
+  }
+}