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(C)
D = [b - c for b, c in zip(B, C)]
D.sort(reverse=True)
ans += sum(D[:k])
print(ans)