Problem 234. Project Euler: Problem 3, Largest prime factor

Created by Doug Hull

Solve Later

The prime factors of 13195 are 5, 7, 13 and 29.

What is the largest prime factor of the number being input, input might be uint64 for large numbers, out must be double precision?

Thank you to Project Euler Problem 3

Solve

Solution Stats

Last solution submitted on Oct 21, 2019

Last 200 Solutions

Problem Comments

Solution Comments

Solution 1632904

1 Comment

1 Comment

Jitesh Kumar on 25 Sep 2018

why it is not accepting the answer ;we cant make such small solutions we are not like professional coder

Solution 26559

2 Comments

2 Comments

Alfonso Nieto-Castanon on 3 Feb 2012

still something fishy with the 3rd problem, example:
x = uint64(321676750829977632);
num2str(x) -> 321676750829977600
rem(x,10) -> 0
euler003(x) -> 83653987
...?

Alfonso Nieto-Castanon on 3 Feb 2012

ok now, it seems this was only an issue with my matlab version (7.7) but was not present in the version running the solvers (which seems to have uint64 arithmetic supported!, man, I need an upgrade...)

Solution 25119

3 Comments

3 Comments

Tomasz on 2 Feb 2012

You should pass the x values as a string. A double precision number cannot resolve all the digits that one needs to solve the test suite problems:

>> x = 321676750829977632;
>> x == x+1
ans =
1

@bmtran (Bryant Tran) on 2 Feb 2012

I agree that there is an issue with the last test suite problem. passing it as a uint64 would work too.

Franck Dernoncourt on 2 Feb 2012

Yep I got "Error: Out of memory. Type HELP MEMORY for your options." :-)

Problem Recent Solvers149

Problem Tags

projecteuler

Problem 234. Project Euler: Problem 3, Largest prime factor

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers149

Suggested Problems

More from this Author52

Problem Tags

Problem 234. Project Euler: Problem 3, Largest prime factor

Solution Stats

Last 200 Solutions

Problem Comments

Solution Comments

Problem Recent Solvers149

Suggested Problems

More from this Author52

Problem Tags

Players