refactor 481

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_481.java

@@ -30,45 +30,49 @@
  */
 public class _481 {
 
-    /**credit: https://discuss.leetcode.com/topic/74917/simple-java-solution-using-one-array-and-two-pointers
-     * Algorithm:
-
-     1. Create an int array a and initialize the first 3 elements with 1, 2, 2.
-     2. Create two pointers head and tail. head points to the number which will be used to generate new numbers.
-     tail points to the next empty position to put the new number. Then keep generating new numbers until tail >= n.
-     3. Need to create the array 1 element more than n to avoid overflow because the last round head might points to a number 2.
-     4. A trick to flip number back and forth between 1 and 2: num = num ^ 3*/
-    public int magicalString(int n) {
-        if (n <= 0) {
-            return 0;
-        }
-        if (n <= 3) {
-            return 1;
-        }
+    public static class Solution1 {
+        /**
+         * credit: https://discuss.leetcode.com/topic/74917/simple-java-solution-using-one-array-and-two-pointers
+         * Algorithm:
+         *
+         * 1. Create an int array a and initialize the first 3 elements with 1, 2, 2.
+         * 2. Create two pointers head and tail. head points to the number which will be used to generate new numbers.
+         * tail points to the next empty position to put the new number. Then keep generating new numbers until tail >= n.
+         * 3. Need to create the array 1 element more than n to avoid overflow because the last round head might points to a number 2.
+         * 4. A trick to flip number back and forth between 1 and 2: num = num ^ 3
+         */
+        public int magicalString(int n) {
+            if (n <= 0) {
+                return 0;
+            }
+            if (n <= 3) {
+                return 1;
+            }
 
-        int[] a = new int[n + 1];
-        a[0] = 1;
-        a[1] = 2;
-        a[2] = 2;
-
-        int head = 2;
-        int tail = 3;
-        int num = 1;
-        int result = 1;
-
-        while (tail < n) {
-            for (int i = 0; i < a[head]; i++) {
-                a[tail] = num;
-                if (num == 1 && tail < n) {
-                    result++;
+            int[] a = new int[n + 1];
+            a[0] = 1;
+            a[1] = 2;
+            a[2] = 2;
+
+            int head = 2;
+            int tail = 3;
+            int num = 1;
+            int result = 1;
+
+            while (tail < n) {
+                for (int i = 0; i < a[head]; i++) {
+                    a[tail] = num;
+                    if (num == 1 && tail < n) {
+                        result++;
+                    }
+                    tail++;
                 }
-                tail++;
+                num = num ^ 3;
+                head++;
             }
-            num = num ^ 3;
-            head++;
-        }
 
-        return result;
+            return result;
+        }
     }
 
 }