#include<iostream>
using namespace std;

int main() {
    int n;
    while (cin >> n) {
        if (n == 0) {
            break;
        }
        int count = 0;
        while (n != 1) {
            if (n % 2) {
                n = (3 * n + 1) / 2;
            } else {
                n = n / 2;
            }
            count++;
        }
        printf("%d\n", count);
    }
}

嵌套了多层while，只要不搞错，此题不难