mirror of
https://github.com/TheAlgorithms/Python.git
synced 2024-12-18 09:10:16 +00:00
9316e7c014
* flake8 --max-line-length=88
* fixup! Format Python code with psf/black push
Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
63 lines
1.6 KiB
Python
63 lines
1.6 KiB
Python
"""
|
|
Greatest Common Divisor.
|
|
|
|
Wikipedia reference: https://en.wikipedia.org/wiki/Greatest_common_divisor
|
|
"""
|
|
|
|
|
|
def greatest_common_divisor(a, b):
|
|
"""
|
|
Calculate Greatest Common Divisor (GCD).
|
|
>>> greatest_common_divisor(24, 40)
|
|
8
|
|
>>> greatest_common_divisor(1, 1)
|
|
1
|
|
>>> greatest_common_divisor(1, 800)
|
|
1
|
|
>>> greatest_common_divisor(11, 37)
|
|
1
|
|
>>> greatest_common_divisor(3, 5)
|
|
1
|
|
>>> greatest_common_divisor(16, 4)
|
|
4
|
|
"""
|
|
return b if a == 0 else greatest_common_divisor(b % a, a)
|
|
|
|
|
|
"""
|
|
Below method is more memory efficient because it does not use the stack (chunk of
|
|
memory). While above method is good, uses more memory for huge numbers because of the
|
|
recursive calls required to calculate the greatest common divisor.
|
|
"""
|
|
|
|
|
|
def gcd_by_iterative(x, y):
|
|
"""
|
|
>>> gcd_by_iterative(24, 40)
|
|
8
|
|
>>> greatest_common_divisor(24, 40) == gcd_by_iterative(24, 40)
|
|
True
|
|
"""
|
|
while y: # --> when y=0 then loop will terminate and return x as final GCD.
|
|
x, y = y, x % y
|
|
return x
|
|
|
|
|
|
def main():
|
|
"""Call Greatest Common Divisor function."""
|
|
try:
|
|
nums = input("Enter two integers separated by comma (,): ").split(",")
|
|
num_1 = int(nums[0])
|
|
num_2 = int(nums[1])
|
|
print(
|
|
f"greatest_common_divisor({num_1}, {num_2}) = "
|
|
f"{greatest_common_divisor(num_1, num_2)}"
|
|
)
|
|
print(f"By iterative gcd({num_1}, {num_2}) = {gcd_by_iterative(num_1, num_2)}")
|
|
except (IndexError, UnboundLocalError, ValueError):
|
|
print("Wrong input")
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main()
|