javascript reduce myflatten code example

Example 1: Javascript flatten array of arrays

var multiDimensionArray = [["a"],["b","c"],["d"]]; //array of arrays
var flatArray = Array.prototype.concat.apply([], multiDimensionArray); //flatten array of arrays
console.log(flatArray); // [ "a","b","c","d"];

Example 2: js ,flat

const numbers = [1, 2, [3, 4, 5, [6, 7]]];
const flatNumbers = numbers.flat(2);

console.log(flatNumbers);