diff --git a/Hard/sudoku-solver/Solution.java b/Hard/sudoku-solver/Solution.java
index 91482bf..bc30cf6 100644
--- a/Hard/sudoku-solver/Solution.java
+++ b/Hard/sudoku-solver/Solution.java
@@ -1,57 +1,68 @@
 class Solution {
-    char[][] BOARD;
+    char[][] Board;
 
     boolean isValid(int row, int col, char num) {
         for (int i = 0; i < 9; i++) {
-            if (BOARD[i][col] == num)
+            if (Board[i][col] == num) {
                 return false;
-            if (BOARD[row][i] == num)
+            }
+
+            if (Board[row][i] == num) {
                 return false;
+            }
         }
 
         row = row - row % 3;
         col = col - col % 3;
-        for (int i = 0; i < 3; i++)
-            for (int j = 0; j < 3; j++)
-                if (BOARD[i + row][j + col] == num)
+        for (int i = 0; i < 3; i++) {
+            for (int j = 0; j < 3; j++) {
+                if (Board[i + row][j + col] == num) {
                     return false;
+                }
+            }
+        }
 
         return true;
     }
 
     int[] nextEmpty() {
-        for (int i = 0; i < 9; i++)
-            for (int j = 0; j < 9; j++)
-                if (BOARD[i][j] == '.')
+        for (int i = 0; i < 9; i++) {
+            for (int j = 0; j < 9; j++) {
+                if (Board[i][j] == '.') {
                     return new int[] { i, j };
+                }
+            }
+        }
 
         return new int[] { -1, -1 };
     }
 
     boolean solver() {
         int[] tmp = nextEmpty();
-        if (tmp[0] == -1)
+        if (tmp[0] == -1) {
             return true;
+        }
 
         int row = tmp[0];
         int col = tmp[1];
 
         for (int i = 1; i <= 9; i++) {
             if (isValid(row, col, (char) (48 + i))) {
-                BOARD[row][col] = (char) (48 + i);
+                Board[row][col] = (char) (48 + i);
 
-                if (solver())
+                if (solver()) {
                     return true;
+                }
             }
 
-            BOARD[row][col] = '.';
+            Board[row][col] = '.';
         }
 
         return false;
     }
 
     public void solveSudoku(char[][] board) {
-        BOARD = board;
+        Board = board;
         solver();
     }
 }