Simple functions don't work :(

[yoop]

Hi. I've been learning javascript for a few days. I got two tasks to solve and I have no idea why they don't work.

First:

function filterEvenNumbers(numbers) {
    let evenNumbers = [];

    for (let i = 0; i < numbers.lenght; i++) {
        if (numbers[i] % 2 === 0) {
            evenNumbers.push(numbers[i]);
        }
    }

    return evenNumbers;
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

function returns an empty array


and second:

function countOccurrences (array, element) {
    let counter = 0;
    for (let i = 0; i < array.lenght; i++) {
        if (array[i] === element){
            counter++;
        }
    }
    return counter;
}
console.log(countOccurrences([2, 1], 1));

functions always returns 0, and in this case it should be 1


Please help me. What's wrong here?

 

[FResher]

It's a keyword bad syntax ... fix your lenght , by length

 

[yoop]

omg... Im so stupid.

Thanks

 

[VBService]

As a curiosity, also check out this record of the "for" loop

function filterEvenNumbers(numbers) {
  const evenNumbers = [];
  for (const number of numbers)
    if (number % 2 === 0)
      evenNumbers.push(number);
  return evenNumbers;
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

or

function filterEvenNumbers(numbers) {
  for (const index in numbers)
    if (numbers[index] % 2 !== 0)
      numbers.splice(index, 1);
  return numbers;
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

did you know about forEach?

function filterEvenNumbers(numbers) {
  const evenNumbers = [];
  numbers.forEach((index) => {
    if (numbers[index] % 2 === 0)
      evenNumbers.push(numbers[index]);
  });
  return evenNumbers;
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

or

function filterEvenNumbers(numbers) {
  numbers.forEach((number, index) => {
    if (number % 2 !== 0)
      numbers.splice(index, 1);
  });
  return numbers;
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

BTW,
I don't know what exactly you are learning, something about:

• Functions
• Loops
• Arrays

if about Arrays, check this

function filterEvenNumbers(numbers) {
  return numbers.filter(number => number % 2 === 0);
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));

or use Array.reduce() in this unusual way

function filterEvenNumbers(numbers) {
  return numbers.reduce((filtered, number) => {
    if (number % 2 === 0)
      filtered.push(number);
    return filtered;
  }, []);
}
console.log(filterEvenNumbers([1, 2, 3, 4, 5, 6]));