#include <bits/stdc++.h>
using namespace std;
#define Yalahwy cin.tie(0), cout.tie(0), cin.sync_with_stdio(0), cout.sync_with_stdio(0);
#define ll long long
#define ld long double
#define EPS 1e-9
#define INF INT_MAX
#define pb push_back
#define pf push_front
#define F first
#define S second
#define all(x) x.begin(),x.end()
#define allr(x) x.rbegin(),x.rend()
#define rep(i, k, n) for(int i=k; i < n ; i++)
#define rev(i, n, k) for(int i = n; i>= k; i--)
#define yes cout << "YES" << endl;
#define no cout << "NO" << endl;
#define NIL -1

// alt + ctrl + l
// يا رب
const ll MOD = 1e9+7;
const ll N = 1e5 + 5;
const ll K = 5;
//const ll M = 100;
double const pi = 3.14159265359;
const int OO=0x3f3f3f3f;
const ll LOO=0x3f3f3f3f3f3f3f3f;
int dx8[] = {+0, +0, -1, +1, +1, +1, -1, -1};
int dy8[] = {-1, +1, +0, +0, +1, -1, +1, -1};
int dx4[] = {+0, +0, -1, +1};
int dy4[] = {-1, +1, +0, +0};
//struct cmp {
//    bool operator()(M const& p1, M const& p2)
//    {
//        return p1.dis > p2.dis;
//    }
//};

int main() {
    Yalahwy
    ll T = 1;
//    cin >> T;
    while (T--) {
        ll n;
        cin >> n;
        map<string , ll> mp;
        for (int i = 0; i < n; ++i) {
            string s;
            cin >> s;
            if(mp.count(s)){
                ll x = mp[s];
                while (true){
                    string a = to_string(x);
                    string g = s + a;
                    if(!mp.count(g)){
                        mp[g]++;
                        cout << g << '\n';
                        break;
                    }
                    x++;
                }
                mp[s] = x + 1;
            }
            else{
                cout << "ok" << '\n';
                mp[s]++;
            }
        }
    }
}