#include<cstdio>
#include<iostream>
#include<algorithm>
using namespace std;
int n,cnt;
struct wifi
{
    string s;
    int id;
} p[1005];
int find(string ad)
{
    for (int i = 1;i <= cnt;i++)
    {
        if (p[i].s == ad)
            return p[i].id;
    }
    return -1;
}

bool chk(string ad)
{
    int cnt1 = 0,cnt2 = 0;
    for (int i = 0;i < ad.size();i++)
    {
        if (ad[i] == '.') cnt1++;
        else if (ad[i] == ':')
        {
            cnt2++;
            if (cnt1 < 3) return false;
        }
        else if (ad[i] < '0' | ad[i] > '9') return false;
    }
    if (cnt1 != 3 || cnt2 != 1) return false;
    if (ad[((int)(ad.size())) - 1] == ':') return false;
    int j = 0;
    for (int i = 1;i <= 5;i++)
    {
        if (ad[j] == '.' || ad[j] == ':') return false;
        if (ad[j] == '0' && '0' <= ad[j+1] && ad[j+1] <= '9') return false;
        long long num = 0;
        while(j < ad.size() && '0' <= ad[j] && ad[j] <= '9')
        {
            num = num * 10 + (ad[j] - '0');
            j++;
        }
        if (i <= 4 && num > 255 || num > 65535) return false;
        j++;
    }
    return true;
}
int main(){
	ios::sync_with_stdio(false);
	cin.tie(0);
	cin >> n;
	for (int i = 1;i <= n;i++)
	{
	    string op,ad;
	    cin >> op >> ad;
	    if (!chk(ad))
	    {
	        cout << "ERR\n";
	        continue;
	    }
	    if (op == "Server")
	    {
	        if (find(ad) != -1)
	        {
	            cout << "FAIL\n";
	        }
	        else
	        {
	            cout << "OK\n";
	            p[++cnt] = {ad,i};
	        }
	    }
	    else
	    {
	        int id = find(ad);
	        if (id != -1) cout << id << "\n";
	        else cout << "FAIL\n";
	    }
	}
	return 0;
}