Given a number, find the sum of all the unique multiples of particular numbers up to but not including that number.
If we list all the natural numbers below 20 that are multiples of 3 or 5, we get 3, 5, 6, 9, 10, 12, 15, and 18.
The sum of these multiples is 78.
Refer to the exercism help page for Rust installation and learning resources.
Execute the tests with:
$ cargo test
All but the first test have been ignored. After you get the first test to
pass, open the tests source file wich is located in the tests
directory
and remove the #[ignore]
flag from the next test and get the tests to pass
again. Each separate test is a function with #[test]
flag above it.
Continue, until you pass every test.
If you wish to run all tests without editing the tests source file, use:
$ cargo test -- --ignored
To run a specific test, for example some_test
, you can use:
$ cargo test some_test
If the specfic test is ignored use:
$ cargo test some_test -- --ignored
To learn more about Rust tests refer to the online test documentation
Make sure to read the Modules chapter if you haven't already, it will help you with organizing your files.
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A variation on Problem 1 at Project Euler http://projecteuler.net/problem=1
It's possible to submit an incomplete solution so you can see how others have completed the exercise.
extern crate sum_of_multiples;
use sum_of_multiples::*;
#[test]
fn multiples_one() {
assert_eq!(0, sum_of_multiples(1, &[3, 5]))
}
#[test]
#[ignore]
fn multiples_two() {
assert_eq!(3, sum_of_multiples(4, &[3, 5]))
}
#[test]
#[ignore]
fn multiples_three() {
assert_eq!(23, sum_of_multiples(10, &[3, 5]))
}
#[test]
#[ignore]
fn multiples_four() {
assert_eq!(2318, sum_of_multiples(100, &[3, 5]))
}
#[test]
#[ignore]
fn multiples_five() {
assert_eq!(233168, sum_of_multiples(1000, &[3, 5]))
}
#[test]
#[ignore]
fn multiples_six() {
assert_eq!(51, sum_of_multiples(20, &[7, 13, 17]))
}
#[test]
#[ignore]
fn multiples_seven() {
assert_eq!(30, sum_of_multiples(15, &[4, 6]))
}
#[test]
#[ignore]
fn multiples_eight() {
assert_eq!(4419, sum_of_multiples(150, &[5, 6, 8]))
}
#[test]
#[ignore]
fn multiples_nine() {
assert_eq!(275, sum_of_multiples(51, &[5, 25]))
}
#[test]
#[ignore]
fn multiples_ten() {
assert_eq!(2203160, sum_of_multiples(10000, &[43, 47]))
}
#[test]
#[ignore]
fn multiples_eleven() {
assert_eq!(4950, sum_of_multiples(100, &[1]))
}
#[test]
#[ignore]
fn multiples_twelve() {
assert_eq!(0, sum_of_multiples(10000, &[]))
}
pub fn sum_of_multiples(upto: isize, numbers: &[isize]) -> isize {
let mut res = Vec::new();
for target in numbers {
for i in 1..upto {
if i % *target == 0 && !res.contains(&i) {
res.push(i);
}
}
}
res.iter().fold(0, |a, b| a + b)
}
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