def smallest_multiple(start, end): if (start > end): return -1 i = 0 while (True): i += 20 # start incrementing a number until we find the smallest multiple for j in range(start, end + 1): # for each number, run a for loop to see if it is the smallest multiple if i % j > 0: break if j == end and i % j == 0: return i print(smallest_multiple(1,20))