While traveling at New York, Aftermath finds a new vending machine. This machine
can only Accept three kinds of coins: 1$, 2$ and 3$. However, he has only a cheque
of N$. He has to enter a bank to exchange it for cash. Now he is interested in
the problem: how many ways can the bank exchanges the cheque for cash? But he
is not smart enough to solve this problem. He asks you for help.
Given a cheque of N$(0<n<=10^9), calculate the number of different ways
to exchange the cheque. The input is ended by 0.