#include <bits/stdc++.h>

using namespace std;
int w[5];
bool check(string addr){
    memset(w, -1, sizeof w);
    sscanf(addr.c_str(), "%d.%d.%d.%d:%d", &w[0], &w[1], &w[2], &w[3], &w[4]);

    char str[100];
    sprintf(str, "%d.%d.%d.%d:%d", w[0], w[1], w[2], w[3], w[4]);
    if (str != addr) return false;
    for (int i = 0; i < 5; i++){
        if (w[i] < 0) return false;
        if (i < 4 && w[i] > 255) return false;
        if (i == 4 && w[i] > 65535) return false;
    }
    return true;
}
int main() {
    //配置从文本文件读入数据
    freopen("network.in","r", stdin);
    freopen("network.out","w", stdout);
    int n;
    cin >> n;
    unordered_map<string, int> hash;
    for (int i = 1; i <= n; i++){
        string type, addr;
        cin >> type >> addr;
        if(type=="Server"){
            if(!check(addr))
                puts("ERR");
            else if(hash.count(addr))
                puts("FAIL");
            else{
                hash[addr] = i;
                puts("OK");
            }
        }else{
            if(!check(addr))
                puts("ERR");
            else if(!hash.count(addr))
                puts("FAIL");
            else
                cout << hash[addr] << endl;
        }
    }
    return 0;
}