SymmetricTree: add YT link & task desc link, adjust tests naming

Author: andrei-punko

src/main/java/by/andd3dfx/tree/SymmetricTree.java

@@ -5,6 +5,8 @@
 
 /**
  * <pre>
+ * <a href="https://leetcode.com/problems/symmetric-tree/description/">Task description</a>
+ *
  * Given the root of a binary tree, check whether it is a mirror of itself (i.e., symmetric around its center).
  *
  * Example 1:
@@ -17,6 +19,8 @@
  * Input: root = [1,2,2,null,3,null,3]
  * Output: false
  * </pre>
+ *
+ * @see <a href="https://youtu.be/pZJ852c2CAE">Video solution</a>
  */
 public class SymmetricTree {
 

src/test/java/by/andd3dfx/tree/SymmetricTreeTest.java

@@ -8,7 +8,7 @@
 public class SymmetricTreeTest {
 
     @Test
-    public void isSymmetricMirroredLeftNRight() {
+    public void isSymmetricWhenMirroredLeftNRightNodes() {
         TreeNode root = new TreeNode(1,
             new TreeNode(2, new TreeNode(3), new TreeNode(4)),
             new TreeNode(2, new TreeNode(4), new TreeNode(3))
@@ -17,11 +17,11 @@ public void isSymmetricMirroredLeftNRight() {
     }
 
     @Test
-    public void isSymmetricTheSameLeftNRight() {
-        TreeNode root2 = new TreeNode(1,
+    public void isSymmetricWhenTheSameLeftNRightNodes() {
+        TreeNode root = new TreeNode(1,
             new TreeNode(2, null, new TreeNode(3)),
             new TreeNode(2, null, new TreeNode(3))
         );
-        assertThat(SymmetricTree.isSymmetric(root2)).isFalse();
+        assertThat(SymmetricTree.isSymmetric(root)).isFalse();
     }
 }