#include<bits/stdc++.h>
using namespace std;
string s,op;
int n,m;
map<string,int> ap;
bool c(string x){
	long long a,b,c,d,e;
	if (sscanf(s.c_str(), "%lld.%lld.%lld.%lld:%lld", &a, &b, &c, &d, &e) != 5)  return false;
	if(a>=0&&b>=0&&c>=0&&d<=255&e>=0&&e<=65535) return 1;
	else return 0;
}
int main(){
	//freopen("p7911_13.in","r",stdin);
	//freopen("ans.out","w",stdout);
	cin>>n;
	for(int i=1;i<=n;i++){
	    cin>>op>>s;	
		if(!c(s)) {cout<<"ERR\n";continue;}
		else if(op[0]=='S') {
		    if(ap[s]) cout<<"FAIL\n";
			else ap[s]=i,cout<<"OK\n";
		}   
		else if(op[0]=='C'){
			if(!ap[s])cout<<"FAIL\n";
			else cout<<ap[s]<<"\n";
			
		}
	} 
	
	
	
	return 0;
}