diff options
Diffstat (limited to 'other/binary_tree_preorder.rs')
-rw-r--r-- | other/binary_tree_preorder.rs | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/other/binary_tree_preorder.rs b/other/binary_tree_preorder.rs new file mode 100644 index 0000000..da6e0b8 --- /dev/null +++ b/other/binary_tree_preorder.rs @@ -0,0 +1,35 @@ +use std::rc::Rc; +use std::cell::RefCell; +#[derive(Debug, PartialEq, Eq)] +pub struct TreeNode { + pub val: i32, + pub left: Option<Rc<RefCell<TreeNode>>>, + pub right: Option<Rc<RefCell<TreeNode>>>, +} + +impl TreeNode { + #[inline] + pub fn new(val: i32) -> Self { + TreeNode { + val, left: None, + right: None + } + } +} + +struct Solution; + +impl Solution { + pub fn preorder_traversal(root: Option<Rc<RefCell<TreeNode>>>) -> Vec<i32> { + let mut ans: Vec<i32> = Vec::new(); + let mut stack: Vec<Option<Rc<RefCell<TreeNode>>>> = vec![root]; + while let Some(last) = stack.pop() { + if let Some(n) = last { + ans.push(n.borrow().val); + stack.push(n.borrow().right.clone()); + stack.push(n.borrow().left.clone()); + } + } + ans + } +} |