program nume;
var f,g:text;
    v:array[-10000..10000]of integer;
    n,m,i,j,castig,greutate:integer;
begin
    assign(f,'rucsac.in');
    reset(f);
    assign(g,'rucsac.out');
    rewrite(g);
    readln(f,n,m);

    for i:=1 to n do
       begin
          readln(f,greutate,castig);
          for j:=m downto 1 do
             if (j>=greutate)and(castig+v[j-greutate]>v[j])then
                  v[j]:=castig+v[j-greutate]
                  else
                  break;
       end;
       writeln(g,v[m]);
close(f);
close(g);
end.