C#

void Test(params int[] arguments)
{
}

// first, get the sum of all the numbers
int sum = 0;
foreach(int i in arguments)
{
    sum += i;
}

// then, divide the sum by the number of arguments to return the average
int average = sum / arguments.Length;

public int GetAverage (params int[] nums)
{
// put your code here
//you can get the number of parameter passed
//by calling nums.GetLength

}

	class MyClass<br />
	{<br />
		[DllImport(@"square.dll", EntryPoint="aFunc")]<br />
		<br />
		public static extern void aFunc(float aNum);<br />
<br />
		public static int Main() <br />
		{<br />
			float aNum=20.0F;<br />
			aFunc(aNum);<br />
			Console.WriteLine(aNum);<br />
			return 0;<br />
		}<br />
	}<br />
}

	class MyClass<br />
	{<br />
		[DllImport(@"square.dll", EntryPoint="aFunc")]<br />
		<br />
		unsafe public static extern void aFunc(float xi, out float * xo);<br />
<br />
		public static int Main() {<br />
			float xi=20.0F;<br />
			unsafe {<br />
				float * xo;<br />
				aFunc(xi,out xo);<br />
				Console.WriteLine(*xo);<br />
			}<br />
			return 0;<br />
		}<br />
	}<br />
}