[N-0] refactor 189

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_189.java

@@ -3,52 +3,62 @@
 import java.util.ArrayList;
 import java.util.List;
 
-/**Rotate an array of n elements to the right by k steps.
+import static com.fishercoder.solutions._189.Solution2.rotate_naive;
+
+/**
+ * 189. Rotate Array
+ *
+ * Rotate an array of n elements to the right by k steps.
+ * For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4].
+ * */
 
-For example, with n = 7 and k = 3, the array [1,2,3,4,5,6,7] is rotated to [5,6,7,1,2,3,4].*/
 public class _189 {
 
-    public void rotate(int[] nums, int k) {
-        int len = nums.length;
-        int[] tmp = new int[len];
-        for (int i = 0; i < len; i++) {
-            tmp[(i + k) % len] = nums[i];
-        }
-        for (int i = 0; i < len; i++) {
-            nums[i] = tmp[i];
+    public static class Solution1 {
+        public void rotate(int[] nums, int k) {
+            int len = nums.length;
+            int[] tmp = new int[len];
+            for (int i = 0; i < len; i++) {
+                tmp[(i + k) % len] = nums[i];
+            }
+            for (int i = 0; i < len; i++) {
+                nums[i] = tmp[i];
+            }
         }
     }
 
-    /**
-     * My original idea and got AC'ed.
-     * One thing to notice is that when k > nums.length, we'll continue to rotate_naive the array, it just becomes k -= nums.length
-     */
-    public static void rotate_naive(int[] nums, int k) {
-        if (k == 0 || k == nums.length) {
-            return;
-        }
-        if (k > nums.length) {
-            k -= nums.length;
-        }
-        List<Integer> tmp = new ArrayList();
-        int i = 0;
-        if (nums.length - k >= 0) {
-            i = nums.length - k;
-            for (; i < nums.length; i++) {
-                tmp.add(nums[i]);
+    public static class Solution2 {
+        /**
+         * My original idea and got AC'ed.
+         * One thing to notice is that when k > nums.length, we'll continue to rotate_naive the array, it just becomes k -= nums.length
+         */
+        public static void rotate_naive(int[] nums, int k) {
+            if (k == 0 || k == nums.length) {
+                return;
             }
-        } else {
-            i = nums.length - 1;
-            for (; i >= 0; i--) {
-                tmp.add(nums[i]);
+            if (k > nums.length) {
+                k -= nums.length;
             }
+            List<Integer> tmp = new ArrayList();
+            int i = 0;
+            if (nums.length - k >= 0) {
+                i = nums.length - k;
+                for (; i < nums.length; i++) {
+                    tmp.add(nums[i]);
+                }
+            } else {
+                i = nums.length - 1;
+                for (; i >= 0; i--) {
+                    tmp.add(nums[i]);
+                }
 
-        }
-        for (i = 0; i < nums.length - k; i++) {
-            tmp.add(nums[i]);
-        }
-        for (i = 0; i < tmp.size(); i++) {
-            nums[i] = tmp.get(i);
+            }
+            for (i = 0; i < nums.length - k; i++) {
+                tmp.add(nums[i]);
+            }
+            for (i = 0; i < tmp.size(); i++) {
+                nums[i] = tmp.get(i);
+            }
         }
     }