Write a function called smallest_multiple

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2520 is the smallest number that can be divided by each of the numbers from 1 to 10 without any remainder. Write a function called smallest_multiple that returns a uint64, the smallest positive number that is evenly divisible by all of the numbers from 1 to n where n is a positive integer scalar and is the only input argument of the function. If the result would be greater than what can be represented as a uint64, the function returns 0.

Answers (2)

Image Analyst
Image Analyst on 4 Mar 2018
Here is a hint:
function results = smallest_multiple(n)
% Your code goes here
Next step, read this:

Srishti Saha
Srishti Saha on 13 May 2018
Here is a solution that worked for me:
%%alternative solution to smallest multiple
function r = smallest_multiple(k)
r = uint64(1);
for n = 1:k
r = r * (n / gcd(r,n));
if r == intmax('uint64')
r = uint64(0);
Walter Roberson
Walter Roberson on 13 May 2018
Edited: Walter Roberson on 3 Jun 2018
The test is okay except for the case where the smallest multiple is exactly equal to intmax('uint64') which is 18446744073709551615 = 65537*(641*(17*(3*5)*257)*6700417) .
In any case where the result would be bigger than intmax('uint64') then the multiplications in the for loop would "saturate" at exactly intmax('uint64')
Ranil Fernando
Ranil Fernando on 3 Jun 2018
Edited: Ranil Fernando on 3 Jun 2018
My code is working outside the grader for n=13 without taking a longer time. But within the grader it fails for even 2. Someone please give me a hand here.
function multiN = smallest_multiple(n)
mod2N = 0;
multiN = uint64(n);
while all(mod2N) == 0
multiN = multiN + 1;
mod2N = zeros(1,n);
for ii=1:n
if mod(multiN,ii) == 0
mod2N(ii) = 1;
elseif multiN == intmax('uint64')
multiN = uint64(0);

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