Placement Preparationan HCL GUVI product
11. Valid BST Check
Required Input:
213Expected Output:
True
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def is_valid_bst(root):
# Write your logic here
pass
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12. Mirror Tree
Required Input:
123Expected Output:
Mirror created
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def mirror_tree(root):
# Write your logic here
pass
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13. Lowest Common Ancestor
Required Input:
324Expected Output:
3
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def lowest_common_ancestor(root, p, q):
# Write your logic here
pass
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14. Zigzag Level Order Traversal
Required Input:
123Expected Output:
[[1], [3, 2]]
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def zigzag_level_order(root):
# Write your logic here
pass
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15. Right View of Binary Tree
Required Input:
123Expected Output:
[1, 3]
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def right_view(root):
# Write your logic here
pass
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Click Run Button to view compiled output
16. Left View of Binary Tree
Required Input:
123Expected Output:
[1, 2]
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def left_view(root):
# Write your logic here
pass
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17. Root-to-Leaf Paths
Required Input:
123Expected Output:
['1->2', '1->3']
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def root_to_leaf_paths(root):
# Write your logic here
pass
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18. Vertical Order Traversal
Required Input:
123Expected Output:
[[2], [1], [3]]
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def vertical_order(root):
# Write your logic here
pass
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19. Build Tree from Inorder and Preorder
Required Input:
123
213Expected Output:
Tree constructed
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def build_tree(preorder, inorder):
# Write your logic here
pass
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20. Binary Tree to Doubly Linked List
Required Input:
213Expected Output:
DLL created
Code In Python
class TreeNode:
def __init__(self, val):
self.val = val
self.left = None
self.right = None
def tree_to_dll(root):
# Write your logic here
pass
Run Code?
Click Run Button to view compiled output