#include<iostream>
#include<cstdio>
#include<cstdlib>
#include<cstring>
#include<cmath>
#include<vector>
#include<queue>
#include<algorithm>
using namespace std;
const int maxl=1e+4,maxc=2,BASE=‘0‘;

struct Trie
{
 int tot,root,child[maxl][maxc];
 bool flag[maxl];
 Trie()
 	{
 	 memset(child[1],0,sizeof(child[1]));
 	 flag[1]=false;
 	 root=tot=1;
	} 	
 void insert(const char * str)
 	{
 	 int *cur=&root;
 	 for(const char *p=str;*p;++p)
 	 	{
 	 	 cur=&child[*cur][*p-BASE];
 	 	 if(*cur==0)
 	 	 	{
 	 	 	 *cur=++tot;
 	 	 	  memset(child[tot],0,sizeof(child[tot]));
 	 	 	  flag[tot]=false;
 	 	 	}
 	 	
 	 	}
	  flag[*cur]=true;
	}
 bool query(const char *str)
 	{
 	 int *cur=&root;
 	 const char *p;
 	 for(p=str;*p&&*cur;++p)
 	 	{
 	 	 cur=&child[*cur][*p-BASE];
 	 	 if(flag[*cur]==true)return false;
		}
	 if((*cur==0))return true;
	 if(!(*p))return false;
	 	else return true;
	}
};



int main()
{
 bool flagg;
 int tott=0;
 do
 	{
 	 	
	 tott++;
 	 flagg=false;
 	 Trie tr;
 	 char c[1000];
 	 bool ans=true;
 	 int len=0;
 	 while(true)
 	 	{
 	 	 char nowc=getchar();
 	 	 if(nowc==EOF)return 0;
 	 	 if(nowc==‘9‘){flagg=true;getchar();break;}
 	 	 if(nowc!=‘\n‘)c[len++]=nowc;
 	 	 	else
 	 	 		{
 	 	 		 c[len++]=‘\0‘;
 	 	 		 if(!tr.query(c)){ans=false;}
 	 	 		 tr.insert(c);
 	 	 		 len=0;continue;
				}
		}
	 if(ans){printf("Set %d is immediately decodable\n",tott);}
	 	else {printf("Set %d is not immediately decodable\n",tott);}
	} 	while(flagg);
 return 0;
}