Improved task 101.

Author: javadev

src/test/java/g0101_0200/s0101_symmetric_tree/SolutionTest.java

@@ -4,14 +4,20 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 
 import com_github_leetcode.TreeNode;
+import com_github_leetcode.TreeUtils;
+import java.util.Arrays;
 import org.junit.jupiter.api.Test;
 
 class SolutionTest {
     @Test
     void symmetricTree() {
-        TreeNode left = new TreeNode(2, new TreeNode(3), new TreeNode(4));
-        TreeNode right = new TreeNode(2, new TreeNode(4), new TreeNode(3));
-        TreeNode root = new TreeNode(1, left, right);
+        TreeNode root = TreeUtils.constructBinaryTree(Arrays.asList(1, 2, 2, 3, 4, 4, 3));
         assertThat(new Solution().isSymmetric(root), equalTo(true));
     }
+
+    @Test
+    void symmetricTree2() {
+        TreeNode root = TreeUtils.constructBinaryTree(Arrays.asList(1, 2, 2, null, 3, null, 3));
+        assertThat(new Solution().isSymmetric(root), equalTo(false));
+    }
 }