Given a nested array like [1,3,4,[6,7,[8,5],9],2], flatten it to produce a single-dimensional array [1,3,4,6,7,8,5,9,2].

Question

Accepted Answer

Flattening a nested array involves converting a multi-dimensional array into a single-dimensional array.

Use recursion to handle arrays of varying depths. Example: flatten([1, [2, [3, 4]], 5]) returns [1, 2, 3, 4, 5].
Utilize built-in methods like Array.prototype.flat() in JavaScript. Example: [1, [2, 3]].flat() returns [1, 2, 3].
Consider edge cases such as empty arrays or arrays with non-array elements. Example: flatten([]) returns [].

Accepted Answer

// with flatmap
console.log(array.flatMap((e) => e).flat(2));

// recursion
function flatThis(nestedArr) {
  const newArray = [];
  for (let i = 0; i < nestedArr.length; i++) {
    let current = nestedArr[i];
    if (Array.isArray(current)) return flatThis(nestedArr.flat());
    else newArray.push(current);
  }
  return newArray;
}

console.log(flatThis(array));

Accepted Answer

Loop through given array and push array data if it not object. Else loop through inner array. Concept of recursion.

Asked in EPAM Systems and 3 others

Given a nested array like [1,3,4,[6,7,[8,5],9],2], flatten it to produce a single-dimensional array [1,3,4,6,7,8,5,9,2].

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