Project Euler Problem 5 - Solved

Q) 2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder.

What is the smallest positive number that is evenly divisible by all of the numbers from 1 to 20?

Solution: Python: Quite Fast

========================== num = 20 def GCD1(num1,num2): if num1>num2: num1,num2 = num2,num1 x = [m for m in range(2,num1+1) if not (num1%m)] y = [] for n in range(num1,1,-1): if not(num2%n)and (n in x): y.append(n) return y[0] def GCD(num1,num2): if num1>num2: return GCD1(num1-num2,num2) elif num2>num1: return GCD1(num1, num2-num1) else: return num1 def LCM(num1,num2): x = abs(num1*num2) y = GCD(num1,num2) if y == None: ans = x else: ans = x/y return ans def SmallMul(): k = ans = num for i in range(k,k/2,-1): ans = LCM(ans,i) return ans print SmallMul()