#include <bits/stdc++.h>
using namespace std;
using ll = long long;
const int INF = 1e9 + 10;
const ll INFL = 4e18;

int main() {
    int N, K;
    cin >> N >> K;
    ll ans = 0;
    for (int i = 0; i < N; i++) {
        ll a;
        cin >> a;
        ans += a;
    }
    vector<ll> B(N), C(N);
    for (int i = 0; i < N; i++) cin >> B[i];
    for (int i = 0; i < N; i++) {
        cin >> C[i];
        ans += C[i];
        C[i] = B[i] - C[i];
    }
    sort(C.rbegin(), C.rend());
    for (int i = 0; i < K; i++) {
        ans += C[i];
    }
    cout << ans << endl;
}