unit ucomplex;

interface

type complex = object
  r: extended;
  i: extended;
  function length(): extended;
  function squared(): complex;
  function mult(a: complex): complex;
  function power(n: integer): complex;
  procedure update(re: extended; im: extended);
end;

function complex_sum(a: complex; b: complex): complex;

implementation

procedure complex.update(re: extended; im: extended);
begin
  r := re;
  i := im;
end;

function complex.length(): extended;
begin
  length := sqrt(r * r + i * i);
end;

function complex.squared(): complex;
var
  res: complex;
begin
  res.r := sqr(r) - sqr(i);
  res.i := 2 * r * i;
  squared := res;
end;

function complex.mult(a: complex): complex;
var
  res: complex;
begin
  res.r := r * a.r - i * a.i;
  res.i := r * a.i + i * a.r;
  mult := res;
end;

function complex.power(n: integer): complex;
var
  j: integer;
  c, res: complex;
begin
  c.update(r, i);
  res.update(r, i);
  for j := 1 to n - 1 do begin
    res := res.mult(c);
  end;
  power := res;
end;

function complex_sum(a: complex; b: complex): complex;
var
  res: complex;
begin
  res.r := a.r + b.r;
  res.i := a.i + b.i;
  complex_sum := res;
end;

begin
end.