Problem:
Score: 300 points

Problem Statement

In Republic of Atcoder, there are N prefectures, and a total of M cities that belong to those prefectures.

City i is established in year Y_i and belongs to Prefecture P_i.

You can assume that there are no multiple cities that are established in the same year.

It is decided to allocate a 12-digit ID number to each city.

If City i is the x-th established city among the cities that belong to Prefecture i, the first six digits of the ID number of City i is P_i, and the last six digits of the ID number is x.

Here, if P_i or x (or both) has less than six digits, zeros are added to the left until it has six digits.

Find the ID numbers for all the cities.

Note that there can be a prefecture with no cities.

Constraints

1 \leq N \leq 10^5

1 \leq M \leq 10^5

1 \leq P_i \leq N

1 \leq Y_i \leq 10^9

Y_i are all different.

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N M
P_1 Y_1
:
P_M Y_M

Output

Print the ID numbers for all the cities, in ascending order of indices (City 1, City 2, ...).

Sample Input 1

2 3
1 32
2 63
1 12

Sample Output 1

000001000002
000002000001
000001000001

As City 1 is the second established city among the cities that belong to Prefecture 1, its ID number is 000001000002.

As City 2 is the first established city among the cities that belong to Prefecture 2, its ID number is 000002000001.

As City 3 is the first established city among the cities that belong to Prefecture 1, its ID number is 000001000001.

Sample Input 2

2 3
2 55
2 77
2 99

Sample Output 2

000002000001
000002000002
000002000003

Solution in C++14 (GCC 5.4.1) (judge verdict: Time Limit Exceeded)

#include <iostream>
#include <iomanip>
#include <cassert>
#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <algorithm>
#include <string>
#include <sstream>
#include <complex>
#include <vector>
#include <list>
#include <queue>
#include <deque>
#include <stack>
#include <map>
#include <set>
using namespace std;

// int main ()
// {
//     cin.tie(0);
//     ios::sync_with_stdio(false);

//     vector<int> p = vector<int>(pow(10, 5), 0);
//     vector<int> y = vector<int>(pow(10, 5), 0);
//     map<int, vector<int>> sortedYears = {}; // 県毎の､ソート済み年配列
//     int n, m; // 県の数､市の数

//     cin >> n >> m;
//     assert(1 <= n && n <= pow(10, 5));
//     assert(1 <= m && m <= pow(10, 5));

//     for(size_t i = 0; i < m; i++)
//     {
//         cin >> p[i];
//         cin >> y[i];

//         assert(1 <= p[i] && p[i] <= n);
//         assert(1 <= y[i] && y[i] <= pow(10, 9));
        
//         sortedYears[p[i]].push_back(y[i]);
//     }

//     for (auto itr = sortedYears.begin(); itr != sortedYears.end(); itr++)
//     {
//         sort(itr->second.begin(), itr->second.end());
//     }

//     for(size_t i = 0; i < m; i++)
//     {
//         auto years = sortedYears[p[i]];
//         int index = lower_bound(years.begin(), years.end(), y[i]) - years.begin();

//         cout << setfill('0') << setw(6) << p[i];
//         cout << setfill('0') << setw(6) << index + 1;
//         cout << endl;
//     }
// }


// int main ()
// {
//     cin.tie(0);
//     ios::sync_with_stdio(false);

//     // 要素の事前確保が無駄
//     vector<int> p = vector<int>(pow(10, 5), 0);
//     vector<int> y = vector<int>(pow(10, 5), 0);
//     vector<vector<int>> sortedYears = vector<vector<int>>(pow(10, 5));
//     int n, m; // 県の数､市の数

//     cin >> n >> m;
//     assert(1 <= n && n <= pow(10, 5));
//     assert(1 <= m && m <= pow(10, 5));

//     for(size_t i = 0; i < m; i++)
//     {
//         cin >> p[i];
//         cin >> y[i];

//         assert(1 <= p[i] && p[i] <= n);
//         assert(1 <= y[i] && y[i] <= pow(10, 9));
        
//         sortedYears[p[i]].push_back(y[i]);
//     }

//     // 要素数分だけソートしているのが無駄
//     for (auto itr = sortedYears.begin(); itr != sortedYears.end(); itr++)
//     {
//         sort(itr->begin(), itr->end());
//     }

//     for(size_t i = 0; i < m; i++)
//     {
//         auto years = sortedYears[p[i]];
//         int index = lower_bound(years.begin(), years.end(), y[i]) - years.begin();

//         // ここをc言語に変えてみるとか.
//         cout << setfill('0') << setw(6) << p[i];
//         cout << setfill('0') << setw(6) << index + 1;
//         cout << endl;
//     }
// }

// int main ()
// {
//     cin.tie(0);
//     ios::sync_with_stdio(false);

//     vector<int> p = {};
//     vector<int> y = {};
//     vector<vector<int>> sortedYears = vector<vector<int>>(pow(10, 5));
//     int n, m; // 県の数､市の数

//     cin >> n >> m;
//     assert(1 <= n && n <= pow(10, 5));
//     assert(1 <= m && m <= pow(10, 5));

//     for(size_t i = 0; i < m; i++)
//     {
//         int pi, yi;
//         cin >> pi;
//         cin >> yi;

//         assert(1 <= pi && pi <= n);
//         assert(1 <= yi && yi <= pow(10, 9));
        
//         p.push_back(pi);
//         y.push_back(yi);
//         sortedYears[pi].push_back(yi);
//     }

//     for(size_t i = 0; i < n; i++)
//     {
//         sort(sortedYears[i].begin(), sortedYears[i].end());
//     }

//     for(size_t i = 0; i < m; i++)
//     {
//         auto years = sortedYears[p[i]];
//         int index = lower_bound(years.begin(), years.end(), y[i]) - years.begin();

//         cout << setfill('0') << setw(6) << p[i];
//         cout << setfill('0') << setw(6) << index + 1;
//         cout << endl;
//     }
// }

// int main ()
// {
//     cin.tie(0);
//     ios::sync_with_stdio(false);

//     vector<int> p = {};
//     vector<int> y = {};
//     vector<vector<int>> sortedYears = vector<vector<int>>(pow(10, 5), vector<int>(0));
//     int n, m; // 県の数､市の数

//     cin >> n >> m;
//     assert(1 <= n && n <= pow(10, 5));
//     assert(1 <= m && m <= pow(10, 5));

//     for(size_t i = 0; i < m; i++)
//     {
//         int pi, yi;
//         cin >> pi;
//         cin >> yi;

//         assert(1 <= pi && pi <= n);
//         assert(1 <= yi && yi <= pow(10, 9));
        
//         p.push_back(pi);
//         y.push_back(yi);
//         sortedYears[pi].push_back(yi);
//     }

//     for(size_t i = 1; i <= n; i++)
//     {
//         sort(sortedYears[i].begin(), sortedYears[i].end());
//     }

//     for(size_t i = 0; i < m; i++)
//     {
//         auto years = sortedYears[p[i]];
//         int index = lower_bound(years.begin(), years.end(), y[i]) - years.begin();

//         long long int number = p[i] * 1000000 + index + 1;
//         printf("%012lld\n", number);
//     }
// }


int main ()
{
    cin.tie(0);
    ios::sync_with_stdio(false);

    vector<int> p = vector<int>(pow(10, 5), 0);
    vector<int> y = vector<int>(pow(10, 5), 0);
    map<int, vector<int>> sortedYears = {}; // 県毎の､ソート済み年配列
    int n, m; // 県の数､市の数

    scanf("%d %d", &n, &m);
    // cin >> n >> m;
    assert(1 <= n && n <= pow(10, 5));
    assert(1 <= m && m <= pow(10, 5));

    for(size_t i = 0; i < m; i++)
    {
        scanf("%d %d", &p[i], &y[i]);
        // cin >> p[i];
        // cin >> y[i];

        assert(1 <= p[i] && p[i] <= n);
        assert(1 <= y[i] && y[i] <= pow(10, 9));
        
        sortedYears[p[i]].push_back(y[i]);
    }

    for (auto itr = sortedYears.begin(); itr != sortedYears.end(); itr++)
    {
        sort(itr->second.begin(), itr->second.end());
    }

    for(size_t i = 0; i < m; i++)
    {
        auto years = sortedYears[p[i]];
        int index = lower_bound(years.begin(), years.end(), y[i]) - years.begin();

        long long int number = static_cast<long long int>(p[i]) * 1000000 + static_cast<long long int>(index + 1);
        printf("%012lld\n", number);

        // cout << setfill('0') << setw(6) << p[i];
        // cout << setfill('0') << setw(6) << index + 1;
        // cout << endl;
    }
}