deep counting.

gistfile1.txt

Array.length will give you the number of top-level elements in an array.

Your task is to create a function deepCount that returns the number of ALL elements within an array, including any within inner-level arrays.

For example:

deepCount([1, 2, 3]);  
//>>>>> 3
deepCount(["x", "y", ["z"]]);  
//>>>>> 4
deepCount([1, 2, [3, 4, [5]]]);  
//>>>>> 7

The input will always be an array.

=============================solution============================================================

function deepCount(a){
  return (Array.from(flatten(a)).length) + depthOf(a);
}

function depthOf(object) {
    var level = 0;
    var key;
    for(key in object) {
        if (!object.hasOwnProperty(key)) continue;

        if(typeof object[key] == 'object'){
            var depth = depthOf(object[key]) + 1;
            level = Math.max(depth, level);
        }
    }
    return level;
}

function *flatten(array) {
  for (elt of array) 
    if (Array.isArray(elt)) yield *flatten(elt);
    else yield elt;
}