Stick Lengths

There are n sticks with some lengths. Your task is to modify the sticks so that each stick has the same length. You can either lengthen and shorten each stick. Both operations cost x where x is the difference between the new and original length. What is the minimum total cost? Input The first input line contains an integer n: the number of sticks. Then there are n integers: p_1,p_2,\ldots,p_n