{Andrei N. MIRESTEAN
"GRIGORE MOISIL" NATIONAL COMPUTER SCIENCE COLLEGE from BRASOV
INTERMEDIATE 5
10 GRADE
CONTEST #1}

var l,h,t,p,dolar:real;
    s:string;
    code:integer;
    k:boolean;

function calculeaza(cost,unitate,h:real):real;
var a:real;
begin
a:=h/unitate;
if a <> trunc(a) then a:=trunc(a) +1;
calculeaza:=a*cost;
k:=true;
end;

begin
assign(input, 'post.in'); reset(input);
assign(output, 'post.out'); rewrite(output);
while not eof do
      begin
      dolar:=0;
      readln(s);
      k:=false;
      val(copy(s,1,pos(',',s)-1),l,code); delete(s,1,pos(',',s)+1);
      val(copy(s,1,pos(',',s)-1),h,code); delete(s,1,pos(',',s)+1);
      val(copy(s,1,pos(',',s)-1),t,code); delete(s,1,pos(',',s)+1);
      val(copy(s,1,length(s)),p,code);

      if ( l >=3.5 ) and (l <= 4.25) and (h >= 3.5) and (h <=6 ) and
           (t >= 0.007) and (t<= 0.016) then
                 dolar:=calculeaza(0.20,0.0625,p)
      else
       if (l > 4.25) and ( l < 6) and (h > 6 ) and (h < 11.5) and
           (t >= 0.007 ) and (t <= 0.016)
             then dolar:=calculeaza(0.30,0.0625,p)
      else
       if (l >=3.5) and ( l<=6.125) and (h >=5) and (h<=11.5) and ( t> 0.016) and ( t< 0.25)
             then dolar:=calculeaza(0.47,0.0625,p)
      else
       if ( l > 6.125) and (l < 24 ) and (h >= 11 ) and ( h <= 18 ) and (t>= 0.25) and (t <=0.5)
            then dolar:=calculeaza(0.56,0.0625,p)
      else
       if ( (l>=24) or  (h> 18) or (t > 0.5) ) and (l+2*(h+t) <= 84 )
            then dolar:=calculeaza(1.5,0.5,p)
      else
       if ( (l>=24) or  (h> 18) or (t > 0.5) ) and (l+2*(h+t) > 84 ) and (l+2*(h+t) <=130 )
            then dolar:=calculeaza(1.75,0.5,p)
      else writeln('UNMAILABLE');

      if k then writeln(dolar:5:2);
      end;

close(input);
close(output);

end