Could not find the main class

[RudeOil]

Hey guys...new to Java so sorry if this is a stupid question.

OS: Windows 7
Code:

class Ex1
{
	public static void main ( String [] args )
	{
		// Set n to be user defined input
		int n = Integer.parseInt(args[0]);
		
		// Loop through n and print required sequence
		for (int i = 0; i < n; i++)
		{
			System.out.print(i+1);			// n
			System.out.print((i+1)^2);		// n^2
			System.out.print((i+1)^3);		// n^3 
		}	
	}
}

In CMD I'm typing:

javac ex1.java

which creates the class in the same folder as ex1.java, then:

java -cp . ex1_1 4

but I get the error: "Could not find or load main class"

Any ideas? Thx for any help :)

[RudeOil]

Actually don't worry..have just solved it! Feel free to delete...

My code should have been java -cp. ex1 4, as opposed to ex1_1!