Fetching algorithms...
root = [1,null,2,3]
[1, 2, 3]
root = [1,2,3,4,5,null,8,null,null,6,7,9]
[1,2,4,5,6,7,3,8,9]
root = []
[]
root = [1]
[1]
Time Complexity
Space Complexity