find winner on a tic tac toe game

Author: anishLearnsToCode

README.md

@@ -328,8 +328,8 @@
 | 1252 | [Cells With Odd Values In Matrix](https://leetcode.com/problems/cells-with-odd-values-in-a-matrix)                                                   |                                                       [![Java](assets/java.png)](src/CellsWithOddValuesInMatrix.java)                                                       |                                                                                                                                   |
 | 1260 | [Shift 2D Grid](https://leetcode.com/problems/shift-2d-grid)                                                                                         |                                                              [![Java](assets/java.png)](src/Shift2DGrid.java)                                                               |                                                                                                                                   |
 | 1266 | [Minimum Time Visiting All Points](https://leetcode.com/problems/minimum-time-visiting-all-points)                                                   |                                                      [![Java](assets/java.png)](src/MinimumTimeVisitingAllPoints.java)                                                      |                                                                                                                                   |
-| 1271 | [Hexspeak](https://leetcode.com/problems/hexspeak)                                                                                                   |                                                                                                                                                                             |                                                                                                                                   |
-| 1275 | [Find Winner On a Tic Tac Toe Game](https://leetcode.com/problems/find-winner-on-a-tic-tac-toe-game)                                                 |                                                                                                                                                                             |                                                                                                                                   |
+| 1271 | 🔒 [Hexspeak](https://leetcode.com/problems/hexspeak)                                                                                                |                                                                                                                                                                             |                                                                                                                                   |
+| 1275 | [Find Winner On a Tic Tac Toe Game](https://leetcode.com/problems/find-winner-on-a-tic-tac-toe-game)                                                 |                                                       [![Java](assets/java.png)](src/FindWinnerOnATicTacToeGame.java)                                                       |                                                                                                                                   |
 | 1281 | [Subtract the Product and Sum of Digits of a Integer](https://leetcode.com/problems/subtract-the-product-and-sum-of-digits-of-an-integer)            |                                                                                                                                                                             |                                                                                                                                   |
 | 1287 | [Element Appearing More Than 25% in Sorted Array](https://leetcode.com/problems/element-appearing-more-than-25-in-sorted-array)                      |                                                                                                                                                                             |                                                                                                                                   |
 | 1290 | [Convert Binary Number In A Linked List to Integer](https://leetcode.com/problems/convert-binary-number-in-a-linked-list-to-integer)                 |                                                                                                                                                                             |                                                                                                                                   |

src/FindWinnerOnATicTacToeGame.java

@@ -0,0 +1,34 @@
+public class FindWinnerOnATicTacToeGame {
+    public String tictactoe(int[][] moves) {
+        String winner = getWinnerInTicTacToe(moves);
+        if ("".equals(winner)) return moves.length == 9 ? "Draw" : "Pending";
+        return winner;
+    }
+
+    private String getWinnerInTicTacToe(int[][] moves) {
+        final int[] rows = new int[3], columns = new int[3];
+        int d1 = 0, d2 = 0, k = 1;
+        for (int[] move : moves) {
+            rows[move[0]] += k;
+            columns[move[1]] += k;
+            if (move[0] == move[1]) d1 += k;
+            if (move[0] == 2 - move[1]) d2 += k;
+            k *= -1;
+        }
+        String result = winnerCheckInArray(rows);
+        if (!"".equals(result)) return result;
+        result = winnerCheckInArray(columns);
+        if (!"".equals(result)) return result;
+        if (d1 == 3 || d2 == 3) return "A";
+        if (d1 == -3 || d2 == -3) return "B";
+        return "";
+    }
+
+    private String winnerCheckInArray(int[] array) {
+        for (int element : array) {
+            if (element == 3) return "A";
+            if (element == -3) return "B";
+        }
+        return "";
+    }
+}