/***************************************************************************************

* *

* CODERBYTE BEGINNER CHALLENGE *

* *

* Additive Persistence *

* Using the JavaScript language, have the function AdditivePersistence(num) take the *

* num parameter being passed which will always be a positive integer and return its *

* additive persistence which is the number of times you must add the digits in num *

* until you reach a single digit. For example: if num is 2718 then your program *

* should return 2 because 2 + 7 + 1 + 8 = 18 and 1 + 8 = 9 and you stop at 9. * *

* *

* SOLUTION *

* The challenge passes a string but it expects us to do Math on it so it needs to *

* be converted to numbers. I will use the base 10 parameter of the toString() *

* function and the map() function to convert each entry in the array to a Number. *

* Then I am going to sum each entry in the array to get a total. I will repeat this *

* until my total is a single digit number. The number of times I sum is returned *

* as the answer. *

* *

* Steps for solution *

* 1) Initialize vars sum and loop *

* 2) Convert str to an array of numbers *

* 3) Loop until the sum of digits in array is a single digit number *

* 4) Return number of loops as answer *

* *

***************************************************************************************/

function AdditivePersistence(num) {

var sum, loop = 0;

var val1 = num.toString(10).split("").map(function(t){return parseInt(t)});

while (val1.length > 1) {

sum = 0;

val1.forEach( function(number) {

sum = sum + number;

});

val1 = sum.toString(10).split("").map(function(t){return parseInt(t)});

loop++;

}

return loop;

}