fn factorial (n: u32) -> u32 {

	if n==0{
		return 1;
	}
	
	let mut product =1;
	
	for i in 1..=n{
		product *=dbg! (i);
	}
	
	 product
}

fn main(){
	let n=-1;
	println! ("{n}! ={}",factorial(n));
}