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# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;


public class Contest
{
	public static void Main()
	{
		int[] a = Array.ConvertAll(Console.ReadLine().Split(' '), new Converter<string,int>(s => int.Parse(s)));

//		int[] b = Array.ConvertAll(Console.ReadLine().Split(' '), new Converter<string,int>(s => int.Parse(s)));
//		int[] c = Array.ConvertAll(Console.ReadLine().Split(' '), new Converter<string,int>(s => int.Parse(s)));
//		int[] d = Array.ConvertAll(Console.ReadLine().Split(' '), new Converter<string,int>(s => int.Parse(s)));

		int m = a[1];
		int[][] e = new int[m][];
		for(int i=0; i<m; i++) {
			e[i] = Array.ConvertAll(Console.ReadLine().Split(' '), new Converter<string,int>(s => int.Parse(s)));
			e[i] = e[i].Concat(new int[] { i }).ToArray();
		}

		Array.Sort(e,(x,y)=>((x[0]==y[0])?(x[1]-y[1]):(x[0]-y[0])));

		string[] ss = new string[m];
		int[] ccnt = new int[a[0]+1];
		for(int i=0; i<m; i++) {
			ccnt[e[i][0]]++;
			ss[e[i][2]] = String.Format("{0:D6}{1:D6}", e[i][0], ccnt[e[i][0]]);
		}

		for(int i=0; i<m; i++) Console.WriteLine(ss[i]);

//		string ans = e[1][1].ToString();

//		Console.WriteLine(ans);
	}
	
	private static int calc_main(int[] a,int[] b,int[] c,int[] d) {



		return 0;
	}




}