n, k = map(int, input().split())
a = list(map(int, input().split()))
b = list(map(int, input().split()))
c = list(map(int, input().split()))
if k == 0:
    print(sum(a) + sum(c))
    exit()
l = sorted([(b[i] - c[i], i) for i in range(n)])
s = {i for _, i in l[-k:]}
ans = 0
for i in range(n):
    ans += a[i]
    if i in s:
        ans += b[i]
    else:
        ans += c[i]
print(ans)