/**

* @param list

* @return sum of those items that are more than the items after them.

* return 0 if list is null

* for example,

* if list = [20, 50, 80, 60, 30], return 80 + 60 = 140

* if list = [70, 50, 80, 10, 40, 40, 20], return 70 + 80 + 40 = 190

* if list = [10, 20, 30, 30, 30], return 0

* if list = [], return 0

*/

public static int sumItemsMoreThanNext(ArrayList list) {

return 0; //to be completed

}