#include <iostream>
#include <iomanip>
#include <queue>
#include <vector>
#include <cmath>
#include <algorithm>
#include <cstring>
#include <bitset>
#include <set>
#include <cstdio>
#include <string>
#include <stack>
#include <map>
#include <sstream>

#define ll long long
#define sz(s) (int)s.size()
#define all(x) x.begin(), x.end()
using namespace std;
void AIA()
{
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
}
void file()
{
#ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
}
const int OO = 1e9 + 7;
const long double PI = acos(-1);
int dx[] = {0, 0, 1, -1, 1, -1, 1, -1}, dx4[] = {0, 1, 0, -1};
int dy[] = {1, -1, 0, 0, 1, -1, -1, 1}, dy4[] = {1, 0, -1, 0};
int main()
{
    // Verify Your thought before Coding.
    AIA();
    file();
    int n;
    cin >> n;
    map<string, int> mp;
    while (n--)
    {
        string s;
        cin >> s;
        if (!mp.count(s))
        {
            cout << "ok\n";
            mp[s] = 1;
        }
        else
        {
            mp[s + "" + to_string(mp[s])] = mp[s];
            cout << s << mp[s] << "\n";
            int a = mp[s];
            while (mp.count(s + "" + to_string(a)))
                a++;
            mp[s] = a;
        }
    }
}