refactor 189

Author: fishercoder1534

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

@@ -32,6 +32,10 @@
 public class _189 {
 
   public static class Solution1 {
+    /**
+     * O(n) space
+     * O(n) time
+     * */
     public void rotate(int[] nums, int k) {
       int len = nums.length;
       int[] tmp = new int[len];
@@ -45,9 +49,26 @@ public void rotate(int[] nums, int k) {
   }
 
   public static class Solution2 {
+    /**
+     * O(1) space
+     * O(n) time
+     * */
+    public void rotate(int[] nums, int k) {
+      int tmp;
+      for (int i = 0; i < k; i++) {
+        tmp = nums[nums.length - 1];
+        for (int j = nums.length - 1; j > 0; j--) {
+          nums[j] = nums[j - 1];
+        }
+        nums[0] = tmp;
+      }
+    }
+  }
+
+  public static class Solution3 {
     /**
      * 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
+     * One thing to notice is that when k > nums.length, we'll continue to rotate the array, it just becomes k -= nums.length
      */
     public static void rotate(int[] nums, int k) {
       if (k == 0 || k == nums.length) {
@@ -77,18 +98,4 @@ public static void rotate(int[] nums, int k) {
       }
     }
   }
-
-   public static class Solution3 {
-    public void rotate(int[] nums, int k) {
-        int tmp;
-        for (int i = 0; i < k; i++) {
-            tmp = nums[nums.length - 1];
-            for (int j = nums.length - 1; j > 0; j--) {
-              nums[j] = nums[j - 1];
-            }
-            nums[0] = tmp;
-        }
-    }
-  }
-
 }

src/test/java/com/fishercoder/_189Test.java

@@ -6,19 +6,39 @@
 import org.junit.Test;
 
 public class _189Test {
-  private static _189.Solution1 solution1;
-  private static int[] nums;
+    private static _189.Solution1 solution1;
+    private static _189.Solution2 solution2;
+    private static _189.Solution3 solution3;
+    private static int[] nums;
 
-  @BeforeClass
-  public static void setup() {
-    solution1 = new _189.Solution1();
-  }
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _189.Solution1();
+        solution2 = new _189.Solution2();
+        solution3 = new _189.Solution3();
+    }
 
-  @Test
-  public void test1() {
-    nums = new int[] {1, 2, 3};
+    @Test
+    public void test1() {
+        nums = new int[]{1, 2, 3};
 
-    solution1.rotate(nums, 1);
-    CommonUtils.printArray(nums);
-  }
+        solution1.rotate(nums, 1);
+        CommonUtils.printArray(nums);
+    }
+
+    @Test
+    public void test2() {
+        nums = new int[]{1, 2, 3};
+
+        solution2.rotate(nums, 1);
+        CommonUtils.printArray(nums);
+    }
+
+    @Test
+    public void test3() {
+        nums = new int[]{1, 2, 3};
+
+        solution3.rotate(nums, 1);
+        CommonUtils.printArray(nums);
+    }
 }