import std.algorithm, std.array, std.container, std.range;
import std.string, std.conv, std.math;
import std.stdio, std.typecons;

alias Tuple!(int, "x", int, "y") point;

void main()
{
  auto rd = readln.split.map!(to!int);
  auto p1 = point(rd[0], rd[1]);
  auto p2 = point(rd[2], rd[3]);
  auto p3 = point(rd[4], rd[5]);

  auto r = call(p1, p2, p3);
  if (r.isNull)
    writeln(-1);
  else
    writeln(r.x, " ", r.y);
}

Nullable!point call(point p1, point p2, point p3)
{
  foreach (ps; [tuple(p1, p2, p3), tuple(p2, p3, p1), tuple(p3, p1, p2)]) {
    auto r = calc(ps.expand);
    if (!r.isNull)
      return r;
  }
  return Nullable!point.init;
}

Nullable!point calc(point p1, point p2, point p3)
{
  auto v12 = point(p1.x - p2.x, p1.y - p2.y);
  auto v23 = point(p2.x - p3.x, p2.y - p3.y);
  if (vabs(v12) == vabs(v23) && vinner_prod(v12, v23) == 0) {
    auto pc = point((p1.x + p3.x) / 2, (p1.y + p3.y) / 2);
    return Nullable!point(point(p1.x + p3.x - p2.x, p1.y + p3.y - p2.y));
  } else {
    return Nullable!point.init;
  }
}

int vabs(point v)
{
  return v.x ^^ 2 + v.y ^^ 2;
}

int vinner_prod(point v1, point v2)
{
  return v1.x * v2.x + v1.y * v2.y;
}