2.1 KiB
Armstrong Numbers
An Armstrong number is a number that is the sum of its own digits each raised to the power of the number of digits.
For example:
- 9 is an Armstrong number, because
9 = 9^1 = 9 - 10 is not an Armstrong number, because
10 != 1^2 + 0^2 = 1 - 153 is an Armstrong number, because:
153 = 1^3 + 5^3 + 3^3 = 1 + 125 + 27 = 153 - 154 is not an Armstrong number, because:
154 != 1^3 + 5^3 + 4^3 = 1 + 125 + 64 = 190
Write some code to determine whether a number is an Armstrong number.
Run the tests with:
bats armstrong_numbers_test.sh
After the first test(s) pass, continue by commenting out or removing the
[[ $BATS_RUN_SKIPPED == true ]] || skip
annotations prepending other tests.
To run all tests, including the ones with skip annotations, run:
BATS_RUN_SKIPPED=true bats armstrong_numbers_test.sh
Source
Wikipedia https://en.wikipedia.org/wiki/Narcissistic_number
External utilities
Bash is a language to write "scripts" -- programs that can call
external tools, such as
sed,
awk,
date
and even programs written in other programming languages,
like Python.
This track does not restrict the usage of these utilities, and as long
as your solution is portable between systems and does not require
installation of third party applications, feel free to use them to solve
the exercise.
For an extra challenge, if you would like to have a better understanding
of the language, try to re-implement the solution in pure Bash,
without using any external tools. Note that there are some types of
problems that bash cannot solve, such as performing floating point
arithmetic and manipulating dates: for those, you must call out to an
external tool.
Submitting Incomplete Solutions
It's possible to submit an incomplete solution so you can see how others have completed the exercise.