program SteelCost;
{ program computing cost of steel needed for several lots of ballbearings
          and one of roller bearings.

R. Rosebrugh
September 30, 1993}

const Price = 0.52;    {price per cc of steel - the units used below}

var   More,BType : Char; {input - loop control and bearing type}
      BBRadius, RBRadius, RBLength : Real;    {input - radii in cm }
      BBLotsize, RBLotSize : Integer;   {input - numbers required}
      BBVolume, RBVolume, Cost  : Real; {output - volumes and cost}

procedure ReadNumbersSizes;
{get input values for lots and dimensions}
begin
     if BType = 'B' then
       begin
            WriteLn ('Type the radius (decimal number) in centimetres');
            WriteLn ('and lot size (whole number) for ball bearings');
            ReadLn (BBRadius,BBLotsize);
            WriteLn
       end{if}
     else
       begin
            WriteLn ('Type the radius and length (decimal numbers) in centimetres');
            WriteLn ('and lot size (whole number) for roller bearings');
            ReadLn (RBRadius,RBLength,RBLotsize);
            WriteLn
       end{else};
end{ReadNumbersSizes};

procedure Steelvolume;
{compute volume of ball bearings and roller bearings}
begin
     if BType = 'B' then
        BBVolume := 4/3*Pi*BBRadius*BBRadius*BBRadius*BBLotsize
     else
        RBVolume := Pi*RBRadius*RBRadius*RBLength*RBLotsize;
end{Steelvolume};

begin{main program}
    Cost := 0.; {initialize accumulating variable}
    WriteLn ('Do you want to compute some costs? Type ''Y'' if so.');
    ReadLn (More);
    WriteLn;
    while More = 'Y' do
      begin
           WriteLn ('What type of lot? Type ''B'' for ball, ''R'' for roller');
           Readln (BType);
           ReadNumbersSizes;
           Steelvolume;
           {compute new cost, depending on type}
           if BType = 'B' then
              Cost := BBVolume * Price + Cost
           else
              Cost := RBVolume * Price + Cost;
           Writeln ('Another lot?');
           ReadLn (More);
           WriteLn;
      end;{while More}
     WriteLn ('The total cost is  $', Cost:5:2);
     {Hold output on screen:}
     WriteLn;
     WriteLn('Press return to continue');
     ReadLn;
end.