最大公约数

gcd.py

def gcd(i, j):
    while i != 0:
        if j >= i:
            j -= i
        else:
            i, j = j, i
    return j

i = int(raw_input("i:"))
j = int(raw_input("j:"))
print(gcd(i, j))

isogcd.py

def isogcd(i, j):
    if i == 0: return j
    if j == 0: return i
    while i != j:
        if i > j:
            i -= j
        else:
            j -= i
    return i

i = int(raw_input('i:'))
j = int(raw_input('j:'))
print(isogcd(i, j))