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

diffs = [b - c for b, c in zip(B, C)]
diffs.sort(reverse=True)

ans = sum(A) + sum(C) + sum(diffs[:K])
print(ans)