Codeforces C. Registration system

C. Registration system

time limit per test
5 seconds

memory limit per test
64 megabytes

input
standard input

output
standard output

A new e-mail service "Berlandesk" is going to be opened in Berland in the near future. The site administration wants to launch their project as soon as possible, that's why they ask you to help. You're suggested to implement the prototype of site registration
system. The system should work on the following principle.

Each time a new user wants to register, he sends to the system a request with his name. If such a name does
not exist in the system database, it is inserted into the database, and the user gets the response OK, confirming the successful registration.
If the name already exists in the system database, the system makes up a new user name, sends it to the user as a prompt and also
inserts the prompt into the database. The new name is formed by the following rule. Numbers, starting with 1, are appended one after another to name (name1,name2,
...), among these numbers the least i is found so that namei does
not yet exist in the database.

Input

The first line contains number n (1 ≤ n ≤ 105).
The following n lines contain the requests to the system. Each request is a non-empty line, and consists of not more than 32 characters, which are all
lowercase Latin letters.

Output

Print n lines, which are system responses to the requests: OK in
case of successful registration, or a prompt with a new name, if the requested name is already taken.

Sample test(s)

input

4
abacaba
acaba
abacaba
acab

output

OK
OK
abacaba1
OK

input

6
first
first
second
second
third
third

output

OK
first1
OK
second1
OK
third1

#include <iostream>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <algorithm>
#include <cmath>
#include <string>
#include <sstream>
#include <vector>
#include <queue>
#include <set>
#include <map>
#include <ctime>
#define MAXN 1000
#define offset 10000
#define eps 1e-11
#define PI acos(-1.0)//3.14159265358979323846
#define exp 2.718281828
#define mod 1000000007
using namespace std;
typedef long long LL;

int main(){
int n;
while(cin>>n){
map<string,int> m;
for(int i = 0;i<n;i++){
string s;
cin>>s;
int num = m[s]++;
if(num == 0){
cout<<"OK"<<endl;
}else{
cout<<s<<num<<endl;
}
}
}
return 0;
}