题目描述
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.
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, ...).
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.
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
输入格式
见题面 Input 部分
输出格式
见题面 Output 部分