Solution to rust/sum-of-multiples

Author: EphemeralDev

rust/sum-of-multiples/.gitignore

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+# Generated by Cargo
+# will have compiled files and executables
+/target/
+**/*.rs.bk
+
+# Remove Cargo.lock from gitignore if creating an executable, leave it for libraries
+# More information here http://doc.crates.io/guide.html#cargotoml-vs-cargolock
+Cargo.lock

rust/sum-of-multiples/Cargo.toml

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+[package]
+edition = "2021"
+name = "sum-of-multiples"
+version = "1.5.0"

rust/sum-of-multiples/README.md

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+# Sum of Multiples
+
+Welcome to Sum of Multiples on Exercism's Rust Track.
+If you need help running the tests or submitting your code, check out `HELP.md`.
+
+## Instructions
+
+Given a list of factors and a limit, add up all the unique multiples of the factors that are less than the limit.
+All inputs will be greater than or equal to zero.
+
+## Example
+
+Suppose the limit is 20 and the list of factors is [3, 5].
+We need to find the sum of all unique multiples of 3 and 5 that are less than 20.
+
+Multiples of 3 less than 20: 3, 6, 9, 12, 15, 18
+Multiples of 5 less than 20: 5, 10, 15
+
+The unique multiples are: 3, 5, 6, 9, 10, 12, 15, 18
+
+The sum of the unique multiples is: 3 + 5 + 6 + 9 + 10 + 12 + 15 + 18 = 78
+
+So, the answer is 78.
+
+## Source
+
+### Created by
+
+- @IanWhitney
+
+### Contributed to by
+
+- @coriolinus
+- @cwhakes
+- @eddyp
+- @efx
+- @ErikSchierboom
+- @GoneUp
+- @hekrause
+- @leoyvens
+- @lutostag
+- @mkantor
+- @nfiles
+- @petertseng
+- @rofrol
+- @sshine
+- @stringparser
+- @xakon
+- @ZapAnton
+
+### Based on
+
+A variation on Problem 1 at Project Euler - http://projecteuler.net/problem=1

rust/sum-of-multiples/src/lib.rs

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+pub fn sum_of_multiples(limit: u32, factors: &[u32]) -> u32 {
+    (1..limit)
+        .filter(|n| factors.iter().any(|f| f != &0 && n % f == 0))
+        .sum()
+}

rust/sum-of-multiples/tests/sum-of-multiples.rs

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+use sum_of_multiples::*;
+
+#[test]
+fn no_multiples_within_limit() {
+    assert_eq!(0, sum_of_multiples(1, &[3, 5]))
+}
+
+#[test]
+#[ignore]
+fn one_factor_has_multiples_within_limit() {
+    assert_eq!(3, sum_of_multiples(4, &[3, 5]))
+}
+
+#[test]
+#[ignore]
+fn more_than_one_multiple_within_limit() {
+    assert_eq!(9, sum_of_multiples(7, &[3]))
+}
+
+#[test]
+#[ignore]
+fn more_than_one_factor_with_multiples_within_limit() {
+    assert_eq!(23, sum_of_multiples(10, &[3, 5]))
+}
+
+#[test]
+#[ignore]
+fn each_multiple_is_only_counted_once() {
+    assert_eq!(2318, sum_of_multiples(100, &[3, 5]))
+}
+
+#[test]
+#[ignore]
+fn a_much_larger_limit() {
+    assert_eq!(233_168, sum_of_multiples(1000, &[3, 5]))
+}
+
+#[test]
+#[ignore]
+fn three_factors() {
+    assert_eq!(51, sum_of_multiples(20, &[7, 13, 17]))
+}
+
+#[test]
+#[ignore]
+fn factors_not_relatively_prime() {
+    assert_eq!(30, sum_of_multiples(15, &[4, 6]))
+}
+
+#[test]
+#[ignore]
+fn some_pairs_of_factors_relatively_prime_and_some_not() {
+    assert_eq!(4419, sum_of_multiples(150, &[5, 6, 8]))
+}
+
+#[test]
+#[ignore]
+fn one_factor_is_a_multiple_of_another() {
+    assert_eq!(275, sum_of_multiples(51, &[5, 25]))
+}
+
+#[test]
+#[ignore]
+fn much_larger_factors() {
+    assert_eq!(2_203_160, sum_of_multiples(10_000, &[43, 47]))
+}
+
+#[test]
+#[ignore]
+fn all_numbers_are_multiples_of_1() {
+    assert_eq!(4950, sum_of_multiples(100, &[1]))
+}
+
+#[test]
+#[ignore]
+fn no_factors_means_an_empty_sum() {
+    assert_eq!(0, sum_of_multiples(10_000, &[]))
+}
+
+#[test]
+#[ignore]
+fn the_only_multiple_of_0_is_0() {
+    assert_eq!(0, sum_of_multiples(1, &[0]))
+}
+
+#[test]
+#[ignore]
+fn the_factor_0_does_not_affect_the_sum_of_multiples_of_other_factors() {
+    assert_eq!(3, sum_of_multiples(4, &[3, 0]))
+}
+
+#[test]
+#[ignore]
+fn solutions_using_include_exclude_must_extend_to_cardinality_greater_than_3() {
+    assert_eq!(39_614_537, sum_of_multiples(10_000, &[2, 3, 5, 7, 11]))
+}