| import unittest | |
| from tree import TreeNode | |
| class Solution: | |
| def widthOfBinaryTree(self, root): | |
| """ | |
| :type root: TreeNode | |
| :rtype: int | |
| """ | |
| if not root: | |
| return 0 | |
| result = 1 | |
| q = [(root, 0)] | |
| while q: | |
| result = max(result, q[-1][1] - q[0][1] + 1) | |
| next_q = [] | |
| for node, i in q: | |
| if node.left: | |
| next_q.append((node.left, i << 1)) | |
| if node.right: | |
| next_q.append((node.right, (i << 1) + 1)) | |
| q = next_q | |
| return result | |
| class Test(unittest.TestCase): | |
| def test_serialize(self): | |
| self._test([1, 3, 2, 5, None, None, 9, 6, None, None, 7], 8) | |
| def _test(self, root, expected): | |
| root = TreeNode.from_array(root) | |
| actual = Solution().widthOfBinaryTree(root) | |
| self.assertEqual(expected, actual) | |
| if __name__ == '__main__': | |
| unittest.main() | |