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: Runtime Error)

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

int main(){
  long a[2];
  long n;
  int i,j,h;
    for(i=0;i<2;i++){
    scanf("%ld",a+i);
  }

  long b[a[1]];
  long c[a[1]];
  long d[a[1]];//番目
   int e[a[0]*a[1]];

  for(i=0;i<a[0]*a[1];i++){
    e[i]=0;
  }
  //int f[a[1]]={};
  for(j=0;j<a[1];j++){
    scanf("%ld",b+j);
    scanf("%ld",c+j);
    e[(b[j]-1)*a[1]+j]=c[j];
    d[j]=1;
    //f[j]++;
    for(h=0;h<a[1];h++){
      if(e[(b[j]-1)*a[1]+h]==0){}
      else if(e[(b[j]-1)*a[1]+h]<c[j]){
        d[j]++;
      }
      else if(e[(b[j]-1)*a[1]+h]>c[j]){
        d[h]++;
      }
    }
  }
for(i=0;i<a[1];i++){
  printf("%06d",b[i]);
  printf("%06d\n",d[i]);
}
// for(i=0;i<a[1]*a[0];i++){
//   printf("%d,",e[i]);
// }
}