#include<cstdio>
using namespace std;
#define MAXN 205 
int main() 
{
    int n,num=0,a[MAXN];
    scanf("%d",&n);
    while(n!=1)
    {
    	a[num]=n;num++;
    	if (n%2==0)n/=2;
    	else n=3*n+1;
    }
    a[num]=1;
    for(int i=num;i>=0;i--);
	    printf("%d",a[i]);
	return 0;    
}

求助