The Coco-Cola Store C(Contest #3 )

Once upon a time, there is a special coco-cola store. If you return three empty bottles to the shop, you’ll get a full bottle of coco-cola to drink. If you have n empty bottles right in your hand, how many full bottles of coco-cola can you drink?

Input There will be at most 10 test cases, each containing a single line with an integer n (1 ≤ n ≤ 100). The input terminates with n = 0, which should not be processed.

Output For each test case, print the number of full bottles of coco-cola that you can drink. Spoiler Let me tell you how to drink 5 full bottles with 10 empty bottles: get 3 full bottles with 9 empty bottles, drink them to get 3 empty bottles, and again get a full bottle from them. Now you have 2 empty bottles. Borrow another empty bottle from the shop, then get another full bottle. Drink it, and finally return this empty bottle to the shop!

Sample Input 3 10 81 0

Sample Output 1 5 40

不懂算法也会做这题，看了题目，在稿纸上写了几步结果，发现它很有规律，

那就是n=1时，f(n)=0；n>1时，f(2)=1,f(3)=1,f(4)=2,···,f(81)=40,···,所以f(n)=n/2;然后就完事了。

#include <iostream>
#include <cstdio>
using namespace std;
int main()
{
int t=0,n;
while(t<10)
{
scanf("%d",&n);
if(n==0)
break;
if(n==1)
printf("0\n");
if(n==2||n>2)
printf("%d\n",n/2);
t++;
}
return 0;

}