Return number of hashes and plus sigs in JavaScript string

user_10193730 0
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I'm working through some JS problems over at edabit and am having some issues with this one. The task asks us to create a function that returns the number of hashes and pluses in a string and return the answer in an array. It returns [0,0] if given an empty string. Examples below.

hashPlusCount("###+") ➞ [3, 1]

hashPlusCount("##+++#") ➞ [3, 3]

hashPlusCount("#+++#+#++#") ➞ [4, 6]

hashPlusCount("") ➞ [0, 0]

Here is the code I came up with using regex.

const hashPlusCount = str =>  
str === "" ? [0,0] :

[str.match(/\#/gi).length,
str.match(/\+/gi).length];

The code works fine on repl.it and outside editors. It even works on the code playground on edabit itself! But on the challenge page, it is returning " Cannot read property 'length' of null at hashPlusCount".

Any help in resolving this and helping me understand what's going on is appreciated.

javascript regex
3 Answers

You need to move the empty search inside of the returning array.

const hashPlusCount = str => [
    (str.match(/\#/gi) || '').length,
    (str.match(/\+/gi) || '').length
];
user_14476750

Another approach is to convert the string into array using Array.from().The Array.from() static method creates a new, shallow-copied Array instance from an array-like or iterable object.

Then, create variables numberofDash and numberofPlush to count number of dash and plus.After that using forEach(), to count the number of dash and plus.

function hashPlusCount(str) {
  let numberofDash = 0,
    numberofPlus = 0;
  Array.from(str).forEach(function (ch) {
    if (ch === "#") {
      numberofDash++;
    }
    if (ch === "+") {
      numberofPlus++;
    }
  });
  return [numberofDash, numberofPlus];
}

console.log(hashPlusCount("###+"));

console.log(hashPlusCount("##+++#"));

console.log(hashPlusCount("#+++#+#++#"));

console.log(hashPlusCount(""));

Admin1 
function hashPlusCount(str) {
    let newstr = str.split('+').join('').length;
    //return newstr;
    let newstr1 = str.split('#').join('').length;
   // return newstr1;
    return [newstr, newstr1]
}
console.log(hashPlusCount("+++++++"))

Output - [ 0, 7 ]

user_190235150
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