curriculum/challenges/english/blocks/learn-tree-traversal-by-building-a-binary-search-tree/65c63fd9b387f0a6c5bf6a72.md
Inside the search method, delete pass and call the helper method _search with the following arguments.
self.root: This is the root of the binary search tree. The search starts from the root.key: This is the value that the user wants to find in the binary search tree.Internally, search delegates the actual search logic to the _search helper method that performs the actual recursive search within the binary search tree.
You should remove the pass keyword from the search method.
({
test: () => {
assert.isFalse(
runPython(
`_Node(_code).find_class("BinarySearchTree").find_function("search").has_pass()`
)
);
},
});
You should call the _search method within the search method.
({ test: () => assert(runPython(`
str(_Node(_code).find_class("BinarySearchTree").find_function("search").find_calls("_search")[0]).startswith("self._search(")
`)) });
You should call the _search method passing self.root and key as the arguments.
({ test: () => assert(runPython(`
_Node(_code).find_class("BinarySearchTree").find_function("search").find_calls("_search")[0].is_equivalent("self._search(self.root, key)")
`)) });
class TreeNode:
def __init__(self, key):
self.key = key
self.left = None
self.right = None
class BinarySearchTree:
def __init__(self):
self.root = None
def _insert(self, node, key):
if node is None:
return TreeNode(key)
if key < node.key:
node.left = self._insert(node.left, key)
elif key > node.key:
node.right = self._insert(node.right, key)
return node
def insert(self, key):
self.root = self._insert(self.root, key)
--fcc-editable-region--
def _search(self, node, key):
if node is None or node.key == key:
return node
if key < node.key:
return self._search(node.left, key)
return self._search(node.right, key)
def search(self, key):
pass
--fcc-editable-region--