#include <bits/stdc++.h>
using namespace std;

int w[5];
bool check(string addr) {
  memset(w, -1, sizeof w);
  // 使用 stringstream 替代 sscanf
  stringstream ss(addr);
  char dot1, dot2, dot3, colon;
  ss >> w[0] >> dot1 >> w[1] >> dot2 >> w[2] >> dot3 >> w[3] >> colon >> w[4];

  // 验证格式是否正确
  if (dot1 != '.' || dot2 != '.' || dot3 != '.' || colon != ':')
    return false;

  // 验证数值范围
  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;
  }

  // 验证转换后的字符串是否与原字符串相同
  stringstream ss2;
  ss2 << w[0] << '.' << w[1] << '.' << w[2] << '.' << w[3] << ':' << w[4];
  return ss2.str() == addr;
}

int main() {
  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;
}