import std.stdio, std.string, std.conv;
import std.range, std.algorithm, std.array, std.typecons, std.container;
import std.math, std.numeric, core.bitop;

alias Pair = Tuple!(int, "y", int, "i");

void main() {
    int n, m;
    scan(n, m);

    auto ans = new string[](m);
    auto ken = new Pair[][](n + 1, 0);

    foreach (i ; 0 .. m) {
        int pi, yi;
        scan(pi, yi);
        ken[pi] ~= Pair(yi, i);
    }

    foreach (i ; 1 .. n + 1) {
        ken[i].sort();
    }

    foreach (i ; 1 .. n + 1) {
        foreach (j, si; ken[i]) {
            ans[si.i] = rightJustify(i.to!string, 6, '0') ~ rightJustify((j+1).to!string, 6, '0');
        }
    }

    writefln("%-(%s\n%)", ans);
}









void scan(T...)(ref T args) {
    import std.stdio : readln;
    import std.algorithm : splitter;
    import std.conv : to;
    import std.range.primitives;

    auto line = readln().splitter();
    foreach (ref arg; args) {
        arg = line.front.to!(typeof(arg));
        line.popFront();
    }
    assert(line.empty);
}


void fillAll(R, T)(ref R arr, T value) {
    static if (is(typeof(arr[] = value))) {
        arr[] = value;
    }
    else {
        foreach (ref e; arr) {
            fillAll(e, value);
        }
    }
}