refactor 530

Author: fishercoder1534

src/main/java/com/fishercoder/solutions/_530.java

@@ -6,6 +6,8 @@
 import java.util.TreeSet;
 
 /**
+ * 530. Minimum Absolute Difference in BST
+ *
  * Given a binary search tree with non-negative values, find the minimum absolute difference between values of any two nodes.
 
  Example:
@@ -27,29 +29,31 @@
  */
 public class _530 {
 
-    public int getMinimumDifference(TreeNode root) {
-        TreeSet<Integer> treeset = new TreeSet<>();
-        treeset.add(root.val);
-        dfs(root, treeset);
-        int diff = Integer.MAX_VALUE;
-        Iterator<Integer> iterator = treeset.iterator();
-        int prev = iterator.next();
-        while (iterator.hasNext()) {
-            int current = iterator.next();
-            diff = Math.min(diff, Math.abs(current - prev));
-            prev = current;
+    public static class Solution1 {
+        public int getMinimumDifference(TreeNode root) {
+            TreeSet<Integer> treeset = new TreeSet<>();
+            treeset.add(root.val);
+            dfs(root, treeset);
+            int diff = Integer.MAX_VALUE;
+            Iterator<Integer> iterator = treeset.iterator();
+            int prev = iterator.next();
+            while (iterator.hasNext()) {
+                int current = iterator.next();
+                diff = Math.min(diff, Math.abs(current - prev));
+                prev = current;
+            }
+            return diff;
         }
-        return diff;
-    }
 
-    private void dfs(TreeNode root, TreeSet<Integer> treeset) {
-        if (root.left != null) {
-            treeset.add(root.left.val);
-            dfs(root.left, treeset);
-        }
-        if (root.right != null) {
-            treeset.add(root.right.val);
-            dfs(root.right, treeset);
+        private void dfs(TreeNode root, TreeSet<Integer> treeset) {
+            if (root.left != null) {
+                treeset.add(root.left.val);
+                dfs(root.left, treeset);
+            }
+            if (root.right != null) {
+                treeset.add(root.right.val);
+                dfs(root.right, treeset);
+            }
         }
     }
 }

src/test/java/com/fishercoder/_530Test.java

@@ -9,14 +9,14 @@
 import static junit.framework.Assert.assertEquals;
 
 public class _530Test {
-    private static _530 test;
+    private static _530.Solution1 solution1;
     private static int expected;
     private static int actual;
     private static TreeNode root;
 
     @BeforeClass
     public static void setup() {
-        test = new _530();
+        solution1 = new _530.Solution1();
     }
 
     @Before
@@ -31,7 +31,7 @@ public void test1() {
         root.right = new TreeNode(3);
         root.right.left = new TreeNode(2);
         expected = 1;
-        actual = test.getMinimumDifference(root);
+        actual = solution1.getMinimumDifference(root);
         assertEquals(expected, actual);
     }
 
@@ -41,7 +41,7 @@ public void test2() {
         root.right = new TreeNode(5);
         root.right.left = new TreeNode(3);
         expected = 2;
-        actual = test.getMinimumDifference(root);
+        actual = solution1.getMinimumDifference(root);
         assertEquals(expected, actual);
     }
 
@@ -54,7 +54,7 @@ public void test3() {
         root.left.right = new TreeNode(445);
         root.right.right = new TreeNode(699);
         expected = 47;
-        actual = test.getMinimumDifference(root);
+        actual = solution1.getMinimumDifference(root);
         assertEquals(expected, actual);
     }
 }