program rucsac;
var castig,alege:array[0..1001,0..1001]of longint;
    gr,c:array[1..1001]of longint;f,t:text;
    i,n,j,g,obiect:integer;
begin
      assign(f,'energii.in');reset(f);
      assign(t,'energii.out');rewrite(t);
      readln(f,n);readln(f,g);
       for i:=1 to n do begin
       read(f,gr[i]);
       readln(f,c[i]);
        end;
         for i:=1 to n do
          for j:=1 to g do
           if gr[i]<=j then
            if c[i]+castig[i-1,j-gr[i]]>castig[i-1,j] then begin
           castig[i,j]:=c[i]+castig[i-1,j-gr[i]];end
                                                      else begin
           castig[i,j]:=castig[i-1,j];end
                                                      else begin
           castig[i,j]:=castig[i-1,j];end;
          i:=n;j:=g;
           writeln(t,castig[i,j]);
           close(t);close(f);
           end.