Power of Two 15 XP Easy

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Given an integer n, return True if it is a power of two: 1, 2, 4, 8, 16, 32, 64, ...

# Powers of 2: 2^0=1, 2^1=2, 2^2=4, 2^3=8, ...
# Key property: keep dividing by 2, if you reach 1 → True

# is_power_of_two(16) → 16/2=8 → 8/2=4 → 4/2=2 → 2/2=1 → True!
# is_power_of_two(6)  → 6/2=3 → 3 is odd → False!

Recursive approach:

Base case 1: n == 1 → return True (2^0 = 1)
Base case 2: n <= 0 or n is odd → return False
Recursive case: return is_power_of_two(n // 2)

🧠 Bit trick: A power of 2 in binary has exactly one '1' bit: n & (n-1) == 0. But let's practice the recursive approach first!

📋 Instructions

Implement `is_power_of_two(n)` recursively. Test with n = 1, 16, 6, 64, 0.

If n == 1, return True. If n <= 0 or n % 2 != 0, return False. Otherwise, recursively check n // 2.

🧪 Test Cases

Input

is_power_of_two(1)

Expected

True

Boolean check

Input

is_power_of_two(16)

Expected

True

Boolean check

Input

is_power_of_two(6)

Expected

False

Boolean check

Input

is_power_of_two(64)

Expected

True

Boolean check

Input

is_power_of_two(0)

Expected

False

Boolean check

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main.py

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Output

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