import java.util.Scanner;

class no586{
	public static void main(String[] args) {
		Scanner stdIn=new Scanner(System.in);
		int p1=stdIn.nextInt(),p2=stdIn.nextInt(),n=stdIn.nextInt(),r,a[]=new int[999],i,s=0;
		for(i=0;i<n;i++) {
			r=stdIn.nextInt();
			a[r-1]++;
		}
		for(i=0;i<999;i++)if(a[i]>0)s+=a[i]-1;
		System.out.print((p1+p2)*s);
	}
}