type vec=record
        a:array of 0..100000;
        end;


var     v:array[1..100000]of vec;
        n,m,i,j,t,x,y:longint;
        w:array[1..100000]of 0..100000;


begin

assign(input,'mesaj4.in');
assign(output,'mesaj4.out');
reset(input);
rewrite(output);

readln(n,m);
for i:=1 to m do
begin
        readln(x,y);
        inc(w[x]);
        setlength(v[x].a,w[x]+1);
        setlength(v[x].a,w[x]+1);
        v[x].a[w[x]]:=y;
end;




end.