class Program01
{
	public static void main(String[] args)
	{
		System.out.println("Háromszög terület, kerület számító program");
		double a = 30;
		double b = 35;
		double c = 40;

		double kerulet = a + b + c;
		
		double alap = 30;
		double mag = 35;
		double terulet = (alap * mag) /2;

		double s = (a + b + c) / 2;
		double terulet2 = Math.sqrt(s*(s-a)*(s-b)*(s-c));
		
		System.out.printf("Kerulet: %.2f\n", kerulet);
		System.out.printf("Terulet: %.2f\n", terulet);
		System.out.printf("Terulet: %.2f\n", terulet2);
	}
}