#include <bits/stdc++.h>
#define ll long long
#define ull unsigned long long
using namespace std;

map < string, int > vis;

bool check(string s)
{
	int len = s.size(), c = 0, t = 0, f = 0;
	for(int i = 0; i < len; i++)
	{
		if(s[i] == 0 && t == 0 && i != f) return 0;
		if(s[i] >= '0' && s[i] <= '9') t = t * 10 + (s[i] - '0');
		else
		{
			if(s[i] == '-') t *= -1;
			else
			{
				c++;
				if(c == 4)
				{
					if(s[i] != ':') return 0;	
				}
				else if(s[i] != '.') return 0;
				if(t > 255 || t < 0) return 0;
				t = 0;
				f = i + 1;
			}
			
		}
	}
	if(t > 65535 || t < 0) return 0;
	return 1;
}

int main()
{
	int t;
	cin >> t;
	for(int i = 1; i <= t; i++)
	{
		string op, s;
		cin >> op >> s;
		if(check(s) == 0)
		{
			cout << "ERR" << endl;
			continue;	
		}
		if(op == "Server")
		{
			if(vis[s] == 0) 
			{
				vis[s] = i;
				cout << "OK" << endl;
			}
			else cout << "FAIL" << endl;
		}
		else
		{
			if(vis[s] == 0) cout << "FAIL" << endl;
			else cout << vis[s] << endl;
		}
	} 
	return 0;
}

WA in #13,14,17,18,19,20,21