p1 = int(input())
p2 = int(input())
n = int(input())
r = [int(input()) for _ in range(n)]

cnt = {}
for i in r:
    if i in cnt:
        cnt[i] += 1
    else:
        cnt[i] = 1

c = 0
for i in cnt:
    if cnt[i] > 1:
        c += (p1+p2) * (cnt[i]-1)

print(c)