Python: Greatest Common Divisor (GCD)

The greatest common divisor (GCD) is the largest integer that evenly divides two numbers. (GCD is also called the Greatest Common Factor.) For example, the GCD of 21 and 14 is 7. This video shows you a beautiful recursive definition of GCD and how to write it in Python.

[kacpermokrzycki]

As a curiosity you can also write
def GCD(a, b):
return a if b==0 else GCD(b, a%b)

if anyone is obsessed with shortcode :))

[mrgfdgfd]

i don't understand how can a%b and b%a can be the same thing

[martinesse]

we do this in school and we haven't taken the recursive functions yet, is there an easier way to write a function like this

[twright]

Do you type in a percentage sign to represent the mod?

[CFGPGFF]

Am i a crappy student if i can't figure this out alone... :(

[spirridd]

It's better to use ternar operator:
def gcd(a, b):
return gcd(b % a, a) if a and b else max(a, b)

[siddietrich]

lol i did it toatly diffrently yours will be faster though they boath work