amazon has multiple delivery centres and delivery wareshouses all over the world! the world is represented by a number line from $-10^9$ to $10^9.$ There are n delivery centres, the ith one at location center$[$i$].$ A location x is called a suitable location for a warehouse if it is possible to bring all the products to that point by travelling a distance of no more than d$.$ At any one time products can be brought from one dleivery center and placed at point x$.$ Hiven the positions of n delivery centres calculate the number of locations in the world. that is calculate the number of points x on the number line $(-10^9<=$ x$<=10^9)$ where the travel distance required to bring all the products to that point is less than or equal to d