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 calculate the number of
different ways to exchange the cheque. The input is ended by 0.

输入格式

Given a cheque of N$(0<n<=10^9), The input is ended by 0.

输出格式

Calculate the number of different ways to exchange the cheque.

样例输入

1 
2
3
0

样例输出

1
2
3 

#include <stdio.h>
int main(){
    long long a,b,t,c;
    while(scanf("%lld",&t)==1&t!=0){
        c=0;      
        for(a=t/3;a>=0;a--){ 
            b=(t-a*3)/2+1; 
            c=c+b; 
        }
        printf("%lld\n",c);
    }
}