const type: point is new struct
    var float: x is 0.0;
    var float: y is 0.0;
  end struct;

const func float: distance (in point: p1, in point: p2) is
  return sqrt((p1.x-p2.x)**2+(p1.y-p2.y)**2);

const func array point: closest_pair (in array point: points) is func
  result
    var array point: result is 0 times point.value;
  local
    var float: dist is 0.0;
    var float: minDistance is Infinity;
    var integer: i is 0;
    var integer: j is 0;
    var integer: savei is 0;
    var integer: savej is 0;
  begin
    for i range 1 to pred(length(points)) do
      for j range succ(i) to length(points) do
        dist := distance(points[i], points[j]);
        if dist < minDistance then
          minDistance := dist;
          savei := i;
          savej := j;
        end if;
      end for;
    end for;
    if minDistance <> Infinity then
      result := [] (points[savei], points[savej]);
    end if;
  end func;