题解 | #汽水瓶#

#include <stdio.h>
#include <string.h>

int main() {
    int n;
    scanf("%d", &n);
    while (n != 0) {
        int count = 0;
        int i, j;
        while (n > 1) {
            i = n % 3;
            j = n / 3;
            if (j == 0) {
                if (i == 3) {
                    count++;
                    n = 1;
                }
                if (i == 2) {
                    count++;
                    n = 0;
                }
                if (i < 2) {
                    n = i;
                }
            } else {
                count += j;
                n = j + i;
            }
        }
        if (count != 0)
            printf("%d\n", count);
        else
            printf("0\n");
        scanf("%d", &n);
    }
    return 0;
}