#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    cout<<n<<" ";
    while (n!=1)
    {
        if(n%2==0)n/=2;
        else n=n*3+1;
        cout<<n<<" ";
    }
    return 0;
}

水一道题

#include<bits/stdc++.h>
using namespace std;
int main()
{
    int n;
    cin>>n;
    cout<<n<<" ";
    while(n>1)
    {
        if(n%2!=0)
        {
            n=n*3+1;
            cout<<n<<" ";
        }
        else
        {
            n/=2;
            cout<<n<<" ";
        }
    }
    return 0;
}