refactor 52

fishercoder1534 · fishercoder1534 · commit 11ce76d0761f · 2020-05-02T06:23:02.000-07:00
diff --git a/src/main/java/com/fishercoder/solutions/_52.java b/src/main/java/com/fishercoder/solutions/_52.java
@@ -1,44 +1,40 @@
 package com.fishercoder.solutions;
 
-/**
- * 52. N-Queens II
- *
- * Follow up for N-Queens problem.
- * Now, instead outputting board configurations, return the total number of distinct solutions.
- */
 public class _52 {
 
-  public static class Solution1 {
-    /**credit: https://discuss.leetcode.com/topic/29626/easiest-java-solution-1ms-98-22*/
-    int count = 0;
+    public static class Solution1 {
+        /**
+         * credit: https://discuss.leetcode.com/topic/29626/easiest-java-solution-1ms-98-22
+         */
+        int count = 0;
 
-    public int totalNQueens(int n) {
-      boolean[] cols = new boolean[n];
-      boolean[] diagnol = new boolean[2 * n];
-      boolean[] antiDiagnol = new boolean[2 * n];
-      backtracking(0, cols, diagnol, antiDiagnol, n);
-      return count;
-    }
+        public int totalNQueens(int n) {
+            boolean[] cols = new boolean[n];
+            boolean[] diagnol = new boolean[2 * n];
+            boolean[] antiDiagnol = new boolean[2 * n];
+            backtracking(0, cols, diagnol, antiDiagnol, n);
+            return count;
+        }
 
-    private void backtracking(int row, boolean[] cols, boolean[] diagnol, boolean[] antiDiagnol,
-        int n) {
-      if (row == n) {
-        count++;
-      }
-      for (int col = 0; col < n; col++) {
-        int x = col - row + n;
-        int y = col + row;
-        if (cols[col] || diagnol[x] || antiDiagnol[y]) {
-          continue;
+        private void backtracking(int row, boolean[] cols, boolean[] diagnol, boolean[] antiDiagnol,
+                                  int n) {
+            if (row == n) {
+                count++;
+            }
+            for (int col = 0; col < n; col++) {
+                int x = col - row + n;
+                int y = col + row;
+                if (cols[col] || diagnol[x] || antiDiagnol[y]) {
+                    continue;
+                }
+                cols[col] = true;
+                diagnol[x] = true;
+                antiDiagnol[y] = true;
+                backtracking(row + 1, cols, diagnol, antiDiagnol, n);
+                cols[col] = false;
+                diagnol[x] = false;
+                antiDiagnol[y] = false;
+            }
         }
-        cols[col] = true;
-        diagnol[x] = true;
-        antiDiagnol[y] = true;
-        backtracking(row + 1, cols, diagnol, antiDiagnol, n);
-        cols[col] = false;
-        diagnol[x] = false;
-        antiDiagnol[y] = false;
-      }
     }
-  }
 }
