from collections import defaultdict
p1 = int(input())
p2 = int(input())
N = int(input())
rec = defaultdict(int)
for i in range(N):
    r = int(input())
    rec[r] += 1

ans = 0
for v in rec.values():
    ans += (v - 1) * (p1 + p2)

print(ans)