i have a set of buttons and i want each one to call the same function with a different parameter but it gives me the error, too many parameters. I am hoping that im just typing something wrong but i can't find it anywhere.

heres the code, well at least as much as i need help on.

Code:
 	button ( 325, 300, easy_roll, easy_norm, easy_roll, difficulty(1), NULL, NULL);
	button ( 325, 350, medium_roll, medium_norm, medium_roll, difficulty(2), NULL, NULL);
	button ( 325, 400, hard_roll, hard_norm, hard_roll, difficulty(3), NULL, NULL);
	button ( 325, 450, impossible_roll, impossible_norm, impossible_roll, difficulty(4), NULL, NULL);

function difficulty(var diff)
{
	start_pan.visible = OFF;
	if ( diff == 1)
	{
		computer_speed = 2;
		ball_speed = 1;
	}
	if ( diff == 2)
	{
		computer_speed = 4;
		ball_speed = 2;
	}
	if ( diff == 3)
	{
		computer_speed = 6;
		ball_speed = 3;
	}
	if ( diff == 4)
	{
		computer_speed = 10;
		ball_speed = 5;
	}
	players_func();
}


i know i can define a different function for all of them but this way would be easier for me.