aboutsummaryrefslogtreecommitdiff
path: root/print_binary_tree.py
diff options
context:
space:
mode:
authorJack Sangdahl <[email protected]>2025-09-02 09:07:00 -0600
committerJack Sangdahl <[email protected]>2025-09-02 09:07:00 -0600
commit44bca90a777b14e8dc145f92f13a760b6949aeae (patch)
tree340b0baaa1ac46280e6815f565ddc249d29ebd1f /print_binary_tree.py
parent57914ff67da704020301e06ab036c92c81ee85ab (diff)
downloadleetcode-44bca90a777b14e8dc145f92f13a760b6949aeae.tar.gz
leetcode-44bca90a777b14e8dc145f92f13a760b6949aeae.zip
655. print binary tree
Diffstat (limited to 'print_binary_tree.py')
-rw-r--r--print_binary_tree.py47
1 files changed, 47 insertions, 0 deletions
diff --git a/print_binary_tree.py b/print_binary_tree.py
new file mode 100644
index 0000000..3c2b147
--- /dev/null
+++ b/print_binary_tree.py
@@ -0,0 +1,47 @@
+# 655. Print Binary Tree
+from leetcode import treenode_build
+
+"""
+given the 'root' of a binary tree, construct a 0-indexed 'm x n' string
+matrix 'res' that represents a formatted layout of the tree. the formatted
+layout matrix should be constructed using the following rules. the height of
+the tree is 'height' and the number of rows 'm' should be equal to 'height +
+1'. the number of columns 'n' should be equal to '2^(height + 1) - 1'. place
+the root node in the middle of the top row (more formally, at location
+'res[0][(n - 1) / 2]'). continue this process until all the nodes in the tree
+have been placed. any empty cells should contain the empty string "". return
+the constructed matrix 'res'.
+"""
+
+
+class Solution(object):
+ def printTree(self, root):
+ """
+ :type root: Optional[TreeNode]
+ :rtype: List[List[str]]
+ """
+
+ def height(node):
+ return 0 if not node else 1 + max(height(node.left), height(node.right))
+
+ def build(node, row, left, right):
+ if not node:
+ return
+ mid = (left + right) / 2
+ self.grid[row][mid] = str(node.val)
+ build(node.left, row + 1, left, mid - 1)
+ build(node.right, row + 1, mid + 1, right)
+
+ h = height(root)
+ w = 2**h - 1
+ self.grid = [[""] * w for i in range(h)]
+ build(node=root, row=0, left=0, right=w - 1)
+ return self.grid
+
+
+if __name__ == "__main__":
+ obj = Solution()
+ r1 = treenode_build(vals=[1, 2])
+ r2 = treenode_build(vals=[1, 2, 3, None, 4])
+ print(obj.printTree(r1))
+ print(obj.printTree(r2))