#define _USE_MATH_DEFINES
#include  <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
#include <string>
#include<math.h>
#include<iomanip>
#include<stdio.h>
#include <stdlib.h>
#include<stdio.h>
#include <queue>
#include<map>
#include <fstream>
#include <sstream>
#include<set>
#include<stack>
#include<time.h>
#include <sys/types.h>
#include <tuple>
#include <numeric>
#include <iterator>

typedef long long int ll;
//#include<bits/stdc++.h>


using namespace std;

ll gcd(ll a, ll b) {
    if (a < b)swap(a, b);
    if (b == 0)return a;
    return gcd(b, a % b);
}
int lcm(int a, int b) {
    return a * b / gcd(a, b);
}




int main()
{

    int Q;
    Q = 1;
    //cin >> Q;   

    while (Q--) {
        int n, m;
        cin >> n >> m;
        ll ans = 0;
        for (int i = 0; i < n; i++) {
            int 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];
        vector<pair<ll, ll>>p(n);
        for (int i = 0; i < n; i++) {
            p[i].first = b[i] - c[i];
            p[i].second = b[i];
        }
        sort(p.rbegin(), p.rend());

        for (int i = 0; i < m; i++) {
            ans += p[i].second;
            
        }
        for (int i = m; i < n; i++)ans += p[i].second - p[i].first;
        cout << ans;
    }
        return 0;
}