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: Wrong Answer)

/*                        ______
 _______   /\     |``\   |        |  /
    |     /  \    |__/   |____    |/
    |    / _ _\   |  \   |        |\
    |   /      \  |   \  |______  |  \

            Dept. of CSE
        Comilla  University

*/
#include<bits/stdc++.h>
#define pi 2*acos(0.0)
#define ll long long
#define FIO ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define Node struct node
#define spc " "
#define  E  2.71828182845904523536
#define pb push_back
#define pp pop_back
#define valid(nx,ny) nx>=0 && nx<n && ny>=0 && ny<m
#define ee endl
#define pii pair<int,int>
#define infinity 10000000000000000
#define mod 1000000007
int fx[]={0,0,+1,-1};
int fy[]={+1,-1,0,0};

using namespace std;
///check n=1;
///check corner case;
const int maX=1e5+1;
vector<ll>Graph[maX],cost[maX];
ll visit[maX];
ll x[10];
ll y[10];

int main()
{
    ll n,m,i,j,cc=0;
    cin>>n>>m;
    map<ll,ll>check;
    map<ll,ll>ara;
    ll p[m],y[m];
    for(i=0;i<m;i++){
        cin>>p[i]>>y[i];
        check[p[i]]++;
        ara[i]=check[p[i]];
    }
    for(i=0;i<m;i++){
        ll x=ara[i];
        ll y=p[i];
        printf("%06ld",x);
        printf("%06ld\n",y);
    }
return 0;
}