Same Tree 15 XP Easy

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Given two binary trees, determine if they are structurally identical and have the same node values.

# Tree 1:    1       Tree 2:    1
#           / \               / \
#          2   3             2   3
# → True (same structure, same values)

# Tree 1:    1       Tree 2:    1
#           /                    \
#          2                      2
# → False (different structure)

Recursive comparison:

If both nodes are None → same (both empty)
If one is None and other isn't → different
If values differ → different
Otherwise: recursively check left subtrees AND right subtrees

📋 Instructions

Implement `is_same_tree(p, q)` that returns True if two trees are identical. Test with identical and different trees.

Base: if not p and not q, return True. If not p or not q, return False. If p.val != q.val, return False. Return is_same_tree(p.left, q.left) and is_same_tree(p.right, q.right).

🧪 Test Cases

Input

is_same_tree(t1, t2)

Expected

True

Boolean check

Input

is_same_tree(t1, t3)

Expected

False

Boolean check

Input

is_same_tree(None, None)

Expected

True

Edge case — null/empty input

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main.py

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Output

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