Profit, loss problem

A1 buys grocery worth rs x1 from A2 and gives rs y note(y>x1) , A2 goes to A3 and buys grocery worth rs x2 and gives A3 note of y, A3 goes to A4 and buys grocery of worth Rs x3 and gives same note to A4, A4 does the same process with A5, A5 with A6,..., An-1 with An. At the end of this chain An gives change of y-xn-1 to An-1, An-1 gives change of y-xn-2,... A2 gives change of y-x1 to A1. A1 goes away taking the grocery and all Ai taking their groceries.Now at the end of this cycle, An notices that note of worth rs y is duplicate and goes to An-1(note- Ai is shopkeeper for i>1 and A1 is primary customer) to take rs y, An-1 goes to An-2 to take y,....A3 goes to A2 to take y.Now what are the losses of Ai?