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<?php

interface Shape
{
  public function getArea(): float;
}

abstract class AbstractShape implements Shape
{
  protected float $width;
  protected float $height;

public function __construct(float $width, float $height)
  {
    $this->width = $width;
    $this->height = $height;
  }

abstract public function getArea(): float;
}

class Rectangle extends AbstractShape
{
  public function __construct(float $width, float $height)
  {
    parent::__construct($width, $height);
  }

public function getArea(): float
  {
    return $this->width * $this->height;
  }
}

class Triangle extends AbstractShape
{
  public function __construct(float $width, float $height)
  {
    parent::__construct($width, $height);
  }

public function getArea(): float
  {
    return 0.5 * $this->width * $this->height;
  }
}

$rectangle = new Rectangle(5, 10);
$triangle = new Triangle(5, 10);

echo "The area of the rectangle is: " . $rectangle->getArea() . "\n";
echo "The area of the triangle is: " . $triangle->getArea() . "\n";

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