C语言：每瓶汽水1元，两个空瓶可以置换一瓶汽水，现在有20元，最多能喝多少瓶汽水。

#include <stdio.h>
#define MAX  20

int main()
{
int money=MAX;
int count=MAX;
while(1)
{
if(money%2!=0)
{
count=count+money-1;
break;
}
else
{
money=money/2;
count+=money;
}
}
printf("%d\n",count);
return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1
#include<stdio.h>

int main()
{
int money = 20;
int total = 20;
int empty = 20;
while (empty >= 2)
{
total = total + empty / 2;
empty = empty / 2 + empty % 2;
}

printf("tatal=%d\n", total);
system("pause");
return 0;
}