add: 另一个树的子树

test/tree/subtree-of-another-tree.test.js

@@ -0,0 +1,7 @@
+import { isSubtree } from '../../src/tree/subtree-of-another-tree'
+import Tree from './Tree'
+
+test('另一个树的子树', () => {
+  expect(isSubtree(Tree.arrToTree([3, 4, 5, 1, 2]), Tree.arrToTree([4, 1, 2]))).toBe(true)
+  expect(isSubtree(Tree.arrToTree([3, 4, 5, 1, 2, null, null, null, null, 0]), Tree.arrToTree([4, 1, 2]))).toBe(false)
+})