from collections import deque

n, m, k = map(int, input().split())
c = [*map(int, input().split())]
a = [*map(int, input().split())]
b = [deque() for _ in range(m)]
ans = [k * a[i] for i in range(m)]
for i, v in enumerate(c):
    b[v - 1].append(i)
    if i >= k:
        if b[v - 1][0] <= i - k:
            b[v - 1].popleft()
    ans[v - 1] = min(ans[v - 1], (k - len(b[v - 1])) * a[v - 1])
print(min(ans))