p1 = int(input())
p2 = int(input())
n = int(input())
r = [0] * n
for i in range(n):
    r[i] = int(input())
db = [e for e in r if r.count(e) > 1]
dbset = set(db)
minus = len(db) - len(dbset)

print(minus * (p1+p2))