//First way Method
public static void main(String[] args) {
		printMessage();
		add(5,9);
		multiply(10, 10);
  
        boolean sum = sum(3,1,5);
		System.out.println(sum);
	}
	
	public static void printMessage() {
		System.out.println("hapy birthday to you: ");
	}
	
	public static void add(int a, int b) {
		System.out.println(a + b);
	}

	public static void multiply(int a, int b) {
		System.out.println(a * b);
	}
}  //output: 
hapy birthday to you: 
14
100

// second way Return Method:
public static void main(String[] args) {
		int sum = add(5,9);
		System.out.println(sum);
		
		int product = multiply(10,10);
		System.out.println(product);
		
	}
	public static int add(int a, int b) {
		return a+b;
	}
	
	public static int multiply(int a, int b) {
		return a * b;
	}
}
//output:
14
100

// String type Method.
public static void main(String[] args) {
		String name = self("my name is mohamed, i am 20 years old!");
		System.out.println(name);
		
		String home = house("My house is very beautifull! ");
		System.out.println(home);
	}
	
	public static String self(String n) {
		return n.toLowerCase();
	}
	
	public static String house(String h) {
		return  h.toUpperCase();
	}
}

//Array Method:
public static void main(String[] args) {
		String array = myArray("This is my aweosme array:");
		System.out.println(array);
		
		int[] awesomeArray = arrayFromInt(4, 6, 7, 8);
		System.out.println(awesomeArray[0]);
		System.out.println(awesomeArray[1]);
		System.out.println(awesomeArray[2]);
		System.out.println(awesomeArray[3]);
	}
	
	public static String myArray(String a) {
		return a.toUpperCase();
	}
	
	public static int[] arrayFromInt(int a, int b, int c, int d) {
		int[] array = new int[4];
		array [0] = a;
		array [1] = b;
		array [2] = c;
		array [3] = d; 
		return array;
		
	}
//output: 
THIS IS MY AWEOSME ARRAY:
4
6
7
8

	public static boolean sum(int x, int y, int z) {
		if(x<=y && y<= z ) {
			return true;
		}
		else {
			return false;
		}
	}
}
//output: 
false