Program Map(output);

type
  real = double;
  tRange = array [0..1] of real;

  tMapRec = record
    mrFrom,
    mrTo: tRange;
    mrScale: real
  end;

  function InitRange(rfrom, rTo: real): tRange;
  begin
    InitRange[0] := rfrom;
    InitRange[1] := rTo;
  end;

  function InitMapRec(const fromRange, toRange: tRange): tMapRec;
  begin
    with InitMapRec do
    begin
      mrFrom := fromRange;
      mrTo := toRange;
      mrScale := (toRange[1] - toRange[0]) / (fromRange[1] - fromRange[0]);
    end;
  end;

  function MapRecRange(const value: real; var MR: tMapRec): real;
  begin
    with MR do
      MapRecRange := (value - mrFrom[0]) * mrScale + mrTo[0];
  end;

  function MapRange(const value: real; const fromRange, toRange: tRange): real;
  begin
    MapRange := (value - fromRange[0]) * (toRange[1] - toRange[0]) /
      (fromRange[1] - fromRange[0]) + toRange[0];
  end;

var
  value: real;
  rFrom, rTo: tRange;
  mr: tMapRec;
  i: longint;

begin
  rFrom := InitRange(0, 10);
  rTo := InitRange(-1, 0);
  mr := InitMapRec(rFrom, rTo);

  for i := 0 to 10 do
  begin
    value := i;
    writeln(i: 4, ' maps to: ', MapRange(value, rFrom, rTo): 10: 6,
      MapRecRange(value, mr): 10: 6);
  end;
end.