Given a nested array, write a function to serialize the array i.e return a one-dimensional array containing all the elements. NOTE: Dont use the .push method.
CODE TEMPLATE
function serialize(arr){
// write your code here
}
let arr = [[true,'true',false],[2],[2,3,4],[],[1]];
console.log(serialize(arr));//[true,'true',false,2,2,3,4,1]