import java.io.IOException;
import java.util.NoSuchElementException;

import java.io.InputStream;

import java.io.PrintWriter;

import java.util.Arrays;
import java.util.HashMap;

@SuppressWarnings("unchecked")
public class Main {
    static HashMap<Integer, Integer> yearidx;

    static int[] P;
    static int[] PCNT;
    static int[] Y;

    static String[] ans;

    static final int MAX_N = 100000;

    public static void main(String[] args) throws IOException {
        PrintWriter out = new PrintWriter(System.out);

        final int N = nextInt();
        final int M = nextInt();

        yearidx = new HashMap<>();

        P = new int[M];
        PCNT = new int[MAX_N];
        Y = new int[M];

        Arrays.fill(PCNT, 0);

        ans = new String[M];

        for (int i = 0; i < M; i++) {
            P[i] = nextInt();
            Y[i] = nextInt();

            yearidx.put(Y[i], i);
        }

        Arrays.sort(Y);

        for (int y : Y) {
            int idx = yearidx.get(y);
            int p = P[idx];

            // PCNT 0-indexed
            ans[idx] =
                String.format("%06d", p)
                + String.format("%06d", ++PCNT[p - 1]);
        }

        for (String s : ans) out.println(s);

        out.flush();
    }

    // FastScanner start
    static final InputStream in = System.in;
    static final byte[] buffer = new byte[1024];
    static int ptr = 0;
    static int buflen = 0;
    static boolean hasNextByte() {
        if (ptr < buflen) {
            return true;
        } else {
            ptr = 0;
            try {
                buflen = in.read(buffer);
            } catch (IOException e) {
                e.printStackTrace();
            }
            if (buflen <= 0) {
                return false;
            }
        }
        return true;
    }
    static int readByte() {
        if (hasNextByte()) return buffer[ptr++];
        else return -1;
    }
    static boolean isPrintableChar(int c) {
        return 33 <= c && c <= 126;
    }
    static boolean hasNext() {
        while (hasNextByte() && !isPrintableChar(buffer[ptr])) ptr++;
        return hasNextByte();
    }
    static String next() {
        if (!hasNext()) throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = readByte();
        while (isPrintableChar(b)) {
            sb.appendCodePoint(b);
            b = readByte();
        }
        return sb.toString();
    }
    static long nextLong() {
        if (!hasNext()) throw new NoSuchElementException();
        long n = 0;
        boolean minus = false;
        int b = readByte();
        if (b == '-') {
            minus = true;
            b = readByte();
        }
        if (b < '0' || '9' < b) {
            throw new NumberFormatException();
        }
        while (true) {
            if ('0' <= b && b <= '9') {
                n *= 10;
                n += b - '0';
            } else if(b == -1 || !isPrintableChar(b)) {
                return minus ? -n : n;
            } else {
                throw new NumberFormatException();
            }
            b = readByte();
        }
    }
    static int nextInt() {
        long nl = nextLong();
        if (nl < Integer.MIN_VALUE || nl > Integer.MAX_VALUE)
            throw new NumberFormatException();
        return (int) nl;
    }
    static double nextDouble() {
        return Double.parseDouble(next());
    }
    // FastScanner end
}


Measured memory_bytes: 122060