ACM ZJU 1808

 

#include <iostream>
#include <string>
#include <vector>
//#include <algorithm>
using namespace std;

int main()
{
    int count = 1;
    string s;
    while(cin>>s)
    {
        vector<string> svec;
        while(s != "9")
        {
            svec.push_back(s);    
            cin>>s;    
        }
        bool tag = false;
        for(vector<string>::iterator it = svec.begin(); it != svec.end(); ++it)
        {
            for(vector<string>::iterator k = (it+1); k != svec.end(); ++k)
            {
                tag = true;
                string s1= *it;
                string s2 = *k;
                int t1 = s1.size();
                int t2 = s2.size();
                int minnumber = (t1>=t2 ? t2:t1);
                
                for(int i=0; i<minnumber; ++i)
                {
                    if (s1[i] != s2[i])
                    {
                        tag = false;
                        break;
                    }
                }
                if (tag == true)
                {
                    break;
                }
            }
            
            if (tag == true)
            {
                break;
            }
        }
        if (tag)
        {
            cout<<"Set "<<count<<" is not immediately decodable"<<endl;
        }
        else
        {
            cout<<"Set "<<count<<" is immediately decodable"<<endl;
        }
        count++;
    }
    return 0;
}