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Hello! Please give me a tip. I desided kata, all tests are passed, but "Random Tests" - is not (( I don't get it why... Kata name "Counting Duplicates", language "c#". Please give me advise what to do. Thanks a lot.
@AlifirenkoVA I don't C#, so I won't be of much but do you have a code snippet by any chance?
Peeps, I'm tryign to solve this kata sort and star, but my random tests fail.
My code:
function twoSort(s) {
// sort the vector
// extract the first value
// add *** between each letter
let sorted = s.sort();
console.log(sorted);
let first = sorted.shift();
console.log(first)
return first.split('').join('***');
} Random tests
Testing for MadeSafeCoin,Steem,Ripple
Log
[ 'MadeSafeCoin', 'Ripple', 'Steem' ]
MadeSafeCoin
✘ It should work for random inputs too - Expected: 'R***i***p***p***l***e', instead got: 'M***a***d***e***S***a***f***e***C***o***i***n'
Completed in 1ms
@dantesolis my code:
public class Kata
{
public static int DuplicateCount(string str)
{
var alphabets = "abcdefghijklmnopqrstuvwxyz123456789".ToCharArray();
int[] nums = new int[alphabets.Length];
var tmp = str.ToLower().ToCharArray();
if (!string.IsNullOrEmpty(str))
{
foreach (var item in tmp)
{
for (int i = 0; i < alphabets.Length; i++)
{
if (item == alphabets[i])
{
nums[i] += 1;
}
}
}
return nums.Count(num => num > 1);
}
else {
return 0;
}
}
public void ShowStr(string str)
{
Console.WriteLine(DuplicateCount(str));
}
}RandomTests
✔ 1 assertion passed
✘ Expected: 8
But was: 7
Completed in 0.047428ms
any ideas what to do?
@AlifirenkoVA I'm at a loss, but hopefully somebody with more creds than me will be able to help?
@dantesolis Do not change the array. Especially do not remove values from the array with
shift.
Many kata authors completely forget that arrays have reference semantics and don't copy them in their random tests.
@bkaestner tried using
splice(0, 1) as well but my random tests keep failing. I'm missing something?
Splice also changes the array.
oh
got it to work with
slice(0, 1) but at a loss on why does it work
Slice does not change the array.
You've solved it, right?
yep as per the docs 'The original array will not be modified.'
thanks for the help, but don't understand very well what you mean by
Many kata authors completely forget that arrays have reference semantics and don't copy them in their random tests.
are you refering to the index of each item in the arry? sorry if stupid question
new to this
:)
Think of random tests this way:
var random_strings = generateRandomStrings();
var reference_solution = function(str){
....
}
Test.assert_equals(yoursolution(random_strings), reference_solution(random_strings));
So, if
yoursolution changes random_strings, the reference_solution will use the changed array.
When you've used
splice, random_strings "lost" "MadeSafeCoin". Therefore, the authors reference solution returned "Ripple" (with stars).
Because
random_strings didn't contain "MadeSafeCoin" anymore.
So what the author should have done:
var random_strings = generateRandomStrings();
var reference_solution = function(str){
....
}
Test.assert_equals(yoursolution(makeCopy(random_strings)), reference_solution(random_strings));
// ^^
@bkaestner got it! thanks this is good to for when I start authoring my katas
@AlifirenkoVA that's just a guess, but you're missing
0 in your alphabet.
By the way, a
String is enumerable.
@bkaestner Wayyy!! Thanks a lot!