class Problem0586:
	def solve(this):
		p1 = int(input())
		p2 = int(input())
		
		n = int(input())
		res = {}
		cnt = 0
		for i in range(n):
			k = int(input())
			if res.get(k, 0) == 0:
				res[k] = 1
			else:
				cnt += p1 + p2
		print(cnt)
		
if __name__ == "__main__":
	problem = Problem0586()
	problem.solve()