n, k = map(int, input().split())
a = list(map(int, input().split()))
b = list(map(int, input().split()))
c = list(map(int, input().split()))

ans = sum(a) + sum(b)
x = [c[i]-b[i] for i in range(n)]
x.sort(reverse=True)
ans += sum(x[:n-k])

print(ans)