题解 | #xxx定律#

#include <iostream>
using namespace std;

int main() {
    int a, b;
    while (cin >> a) 
    { // 注意 while 处理多个 case
     //   cout << a + b << endl;
     if (a == 0) 
     {
       return 0;
     }
     b = 0;
     while (a != 1) 
     {
       if (a % 2 == 0) 
       {
         a /= 2;
         b++;
       }
       else 
       {
         a = (a*3 + 1) / 2;
         b++;
       }
     }
     cout << b <<endl;
     
    }
}
// 64 位输出请用 printf("%lld")