Find Bottom Left Tree Value
Given the root of a binary tree, return the leftmost value in the last row of the tree.
Example 1
2
/ \
1 3Input
root = [2,1,3]Output
1The last row contains values 1 and 3, and the leftmost value is 1.
Example 2
1
/ \
2 3
/ / \
4 5 6
/
7Input
root = [1,2,3,4,null,5,6,null,null,7]Output
7The last row contains value 7, so the leftmost value in the last row is 7.
Constraints
- The number of nodes in the tree is in the range
[1, 10^4]. -2^31 <= Node.val <= 2^31 - 1