from collections import Counter

N,M,K=map(int,input().split())
B=list(map(int,input().split()))
A=list(map(int,input().split()))

MAX=[0]*(M+1)

C=Counter()
for i in range(K):
    C[B[i]]+=1

for c in C:
    MAX[c]=C[c]

for i in range(K,N):
    C[B[i]]+=1
    C[B[i-K]]-=1

    MAX[B[i]]=C[B[i]]

ANS=1<<60

for i in range(1,M+1):
    ANS=min(ANS,(K-MAX[i])*A[i-1])

print(ANS)