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1. Print Numbers 1–1002. Print Even Numbers in Range3. Print Odd Numbers in Range4. Sum of Digits5. Reverse Digits of a Number6. Calculate Factorial (Loop)7. Fibonacci Series8. Palindrome Number Check9. Count Digits in a Number10. GCD of Two Numbers (Loop)11. LCM of Two Numbers (Loop)12. Print Prime Numbers in Range13. Count Prime Numbers in Range14. Check Composite Number15. Power of 2 Checker16. Print Number Pattern17. Print Star Pattern18. Armstrong Numbers in Range19. Strong Numbers in Range20. Sum of Series 1/1 + 1/2 + … + 1/N21. Print Multiplication Series22. Print Pyramid Pattern23. Print Inverted Pyramid Pattern24. Print Floyd's Triangle25. Print Pascal's Triangle

Power of 2 Checker in Python

Check whether a positive integer is a power of 2 using a loop.

BeginnerLoop ProgramsExample 15 of 25
power-of-2-checker.py
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1# Program to check if a number is a power of 2
2

3n = int(input("Enter a positive integer: "))
4

5if n <= 0:
6    print("Please enter a positive integer.")
7else:
8    while n % 2 == 0:
9        n //= 2
10    if n == 1:
11        print("It is a power of 2")
12    else:
13        print("It is not a power of 2")

Output

Enter a positive integer: 16
It is a power of 2

What's going on

We divide by 2 until the number is no longer even; if we eventually get 1, the original number was a power of 2.

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