#include <bits/stdc++.h>

void solve() {
  int N, K; std::cin >> N >> K;
  std::vector<long long> A(N), B(N), C(N);
  for (auto &a : A) std::cin >> a;
  for (auto &b : B) std::cin >> b;
  for (auto &c : C) std::cin >> c;
  long long ans = 0;
  for (auto a : A) ans += a;
  std::vector<std::pair<long long, long long>> P(N);
  for (int i = 0; i < N; i++) P[i] = std::make_pair(B[i]-C[i], i);
  std::sort(P.begin(), P.end(), std::greater<std::pair<long long, long long>>());
  std::vector<bool> solt(N, false);
  for (int i = 0; i < K; i++) solt[P[i].second] = true;
  for (int i = 0; i < N; i++) {
    if (solt[i]) ans += B[i];
    else ans += C[i];
  }
  std::cout << ans << std::endl;
}

int main() {
  std::ios::sync_with_stdio(false);
	std::cin.tie(nullptr);

  int testcases = 1;
  //std::cin >> testcases;
  for (;testcases--;) solve();

  return 0;
}