diff --git a/src/__pycache__/prime_factorization.cpython-312.pyc b/src/__pycache__/prime_factorization.cpython-312.pyc new file mode 100644 index 0000000..1469fb6 Binary files /dev/null and b/src/__pycache__/prime_factorization.cpython-312.pyc differ diff --git a/src/prime_factorization.py b/src/prime_factorization.py new file mode 100644 index 0000000..5261195 --- /dev/null +++ b/src/prime_factorization.py @@ -0,0 +1,68 @@ +def is_prime(n): + """ + Check if a number is prime. + + Args: + n (int): Number to check for primality. + + Returns: + bool: True if the number is prime, False otherwise. + """ + if n < 2: + return False + for i in range(2, int(n**0.5) + 1): + if n % i == 0: + return False + return True + +def prime_factorization(n): + """ + Compute the prime factorization of a given integer. + + Args: + n (int): The number to factorize. + + Returns: + dict: A dictionary of prime factors and their frequencies. + + Raises: + ValueError: If the input is not a positive integer. + """ + # Handle edge cases + if not isinstance(n, int): + raise ValueError("Input must be an integer") + + if n < 0: + raise ValueError("Input must be a non-negative integer") + + if n < 2: + return {} + + # Initialize factors dictionary + factors = {} + + # Validate primality of initial value + if not is_prime(n) or n == 1: + # Handle 2 as a special case to optimize odd number factorization + while n % 2 == 0: + factors[2] = factors.get(2, 0) + 1 + n //= 2 + + # Check odd factors up to square root of n + factor = 3 + while factor * factor <= n: + # Validate primality of factor + if is_prime(factor): + while n % factor == 0: + factors[factor] = factors.get(factor, 0) + 1 + n //= factor + factor += 2 + + # If n is a prime number greater than 2 + if n > 2 and is_prime(n): + factors[n] = factors.get(n, 0) + 1 + else: + # n itself is prime + factors[n] = 1 + + return factors \ No newline at end of file diff --git a/tests/__pycache__/test_prime_factorization.cpython-312-pytest-8.3.5.pyc b/tests/__pycache__/test_prime_factorization.cpython-312-pytest-8.3.5.pyc new file mode 100644 index 0000000..e61807a Binary files /dev/null and b/tests/__pycache__/test_prime_factorization.cpython-312-pytest-8.3.5.pyc differ diff --git a/tests/test_prime_factorization.py b/tests/test_prime_factorization.py new file mode 100644 index 0000000..8ab32f7 --- /dev/null +++ b/tests/test_prime_factorization.py @@ -0,0 +1,59 @@ +import pytest +from src.prime_factorization import prime_factorization, is_prime + +def test_is_prime(): + """Test prime number checking function.""" + assert is_prime(2) == True + assert is_prime(3) == True + assert is_prime(7) == True + assert is_prime(11) == True + assert is_prime(4) == False + assert is_prime(15) == False + assert is_prime(1) == False + assert is_prime(0) == False + +def test_prime_number_factorization(): + """Test factorization of prime numbers.""" + assert prime_factorization(7) == {7: 1} + assert prime_factorization(11) == {11: 1} + assert prime_factorization(13) == {13: 1} + +def test_composite_number_factorization(): + """Test factorization of composite numbers.""" + assert prime_factorization(24) == {2: 3, 3: 1} + assert prime_factorization(100) == {2: 2, 5: 2} + assert prime_factorization(84) == {2: 2, 3: 1, 7: 1} + +def test_edge_cases(): + """Test edge cases like 0, 1, and small numbers.""" + assert prime_factorization(0) == {} + assert prime_factorization(1) == {} + assert prime_factorization(2) == {2: 1} + +def test_error_handling(): + """Test error handling for invalid inputs.""" + with pytest.raises(ValueError): + prime_factorization(-5) + + with pytest.raises(ValueError): + prime_factorization(3.14) + + with pytest.raises(ValueError): + prime_factorization("not a number") + +def test_large_number(): + """Test factorization of a relatively large number.""" + result = prime_factorization(123456) + + # Verify the result contains only prime keys + assert all(is_prime(key) for key in result.keys()) + + # Verify the product of prime factors equals the original number + product = 1 + for prime, freq in result.items(): + product *= (prime ** freq) + assert product == 123456 + + # Verify the number of prime factors + total_factors = sum(result.values()) + assert total_factors > 0 \ No newline at end of file