JavaScript Challenge - Flatten an Array

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This was my go :

function flattenArray(array) {
  let temp = [];
  array.forEach(i=>{
    typeof i === 'object'?temp.push(...i):temp.push(i)
  });
  return temp;
}

console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9]))

// Leave this so we can test your code:
module.exports = flattenArray;```

recurse method

function flatten(item, array) {
  if (Array.isArray(item)) {
    item.forEach((inside) => {
      console.log("Flatten:", inside);
      flatten(inside, array);
    });
  } else {
    console.log("Pushed:", item);
    array.push(item);
  }
}

function flattenArray(array) {
  // Write your code here
  const result = [];
  for (let i = 0; i < array.length; i++) {
    flatten(array[i], result);
  }
  return result;  
}

console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9]))

// Leave this so we can test your code:
module.exports = flattenArray;

Here is one way to do it without taking up too much space:

function flattenArray(array) {
  return array.reduce((acc, cur) => acc.concat(cur), []);
}
function flattenArray(array) {
  var res = [];
  array.map(el => {
    if (typeof el === 'object' && el.length > 0) {
      for (var i = 0; i < el.length; i++) {
        res.push(el[i])
      }
    } else {
      if (el.length !== 0) {
        res.push(el)
      }
    }
  })

  return res;
}

console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9, []]))

// Leave this so we can test your code:
module.exports = flattenArray;

Recursively,

function flattenArray(array, arr=[]) {
  for (let i = 0; i < array.length; i++) {
    const x = array[i]
    if (Array.isArray(x)) {
      flattenArray(x, arr)
    } else {
      arr.push(x)
    }
  }
  return arr
}

console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9]))

// Leave this so we can test your code:
module.exports = flattenArray;

It is rather moot now that we the flat() method. This one uses the spread with .concat()

return [].concat(...array)
function flattenArray(array) {
  let currentIndex = 0;
  let faltArray = [];

  while (currentIndex !== array.length) {
    const instanceOfArray = array[currentIndex] instanceof Array;
    if (!instanceOfArray) {
      faltArray.push(array[currentIndex]);
    }

    if (instanceOfArray) {
      for (const valuesOfSecDemensional of array[currentIndex]) {
        faltArray.push(valuesOfSecDemensional);
      }
    }
    currentIndex++;
  }
  return faltArray;
}
console.log(flattenArray([1, 2, 3, [4, 5], 6, [7, 8], 9]))
// Leave this so we can test your code:
module.exports = flattenArray;
function flattenArray(array) {
  let result = [];
  array.forEach(el =>
  Array.isArray(el) ? el.forEach(elmt =>
   result.push(elmt)) : result.push(el)
  );
  return result;
}

console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9]))

// Leave this so we can test your code:
module.exports = flattenArray;

Using reduce function:

function flattenArray(array) { // Write your code here return array.reduce((acc, val) => acc.concat(val), []); } console.log(flattenArray([1, 2, [3, 4, 5], 6, [7, 8], 9])) // Leave this so we can test your code: module.exports = flattenArray;
function flattenArray(array) {
  let result = [];
  (function flatten(x, r) { Array.isArray(x) ? x.forEach(y => flatten(y, r)) : r.push(x) })(array, result);
  return result;
}