题解 | #汽水瓶#

#include <stdio.h>

//f1 = 0
//f2 = 1;
//f3 = 1+f1;
//f4 = 1+f2;

int main()
{
    unsigned int N = 0;
    unsigned int a = 0;
    unsigned int b = 0;
    unsigned int c = 0;
    while (scanf("%d", &N)) {
        //printf("^^^^%d", N);
        if (N == 0) {
            break;
        }
        while (N > 1) {
            a = N / 3; //已经喝的；
            b = N % 3; //剩余的；
            N = a+b;
            c += a;
            if (N == 2) {
                c++;
                break;
            }

        }
        printf("%d\n", c);
        c = 0;
    }
    return 0;
}