N, M, K = map(int, input().split())
C = [i-1 for i in list(map(int, input().split()))]
A = list(map(int, input().split()))
X = [0] * (M + 1)  # X[j]:=区間の長さKの中にある色jの数
for i in range(K):
    X[C[i]] += 1
ans = 10 ** 15
for i in range(M):
    ans = min(ans, (K - X[i]) * A[i])
for i in range(K,N):
    X[C[i-K]] -= 1
    X[C[i]] += 1
    ans = min(ans, (K - X[C[i]]) * A[C[i]])
print(ans)