An Armstrong number is a number that is the sum of its own digits each raised to the power of the number of digits.
9 = 9^1 = 9
10 != 1^2 + 0^2 = 1
153 = 1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153
154 != 1^3 + 5^3 + 4^3 = 1 + 125 + 64 = 190
Write some code to determine whether a number is an Armstrong number.
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 which is located in the
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 ignored 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 specific 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.
After you have solved the exercise, please consider using the additional utilities, described in the installation guide, to further refine your final solution.
To format your solution, inside the solution directory use
To see, if your solution contains some common ineffective use cases, inside the solution directory use
cargo clippy --all-targets
Generally you should submit all files in which you implemented your solution (
src/lib.rs in most cases). If you are using any external crates, please consider submitting the
Cargo.toml file. This will make the review process faster and clearer.
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