Igor found out discounts in a shop and decided to buy n items. Discounts at the store will last for a week and Igor knows about each item that its price now is ai, and after a week of discounts its price will be bi.

Not all of sellers are honest, so now some products could be more expensive than after a week of discounts.

Igor decided that buy at least k of items now, but wait with the rest of the week in order to save money as much as possible. Your task is to determine the minimum money that Igor can spend to buy all n items.

Input

In the first line there are two positive integer numbers n and k (1 ≤ n ≤ 2·105, 0 ≤ k ≤ n) — total number of items to buy and minimal number of items Igor wants to by right now.

The second line contains sequence of integers a1, a2, ..., an (1 ≤ ai ≤ 104) — prices of items during discounts (i.e. right now).

The third line contains sequence of integers b1, b2, ..., bn (1 ≤ bi ≤ 104) — prices of items after discounts (i.e. after a week).

Output

Print the minimal amount of money Igor will spend to buy all n items. Remember, he should buy at least k items right now.

Examples

Input

3 1
5 4 6
3 1 5


Output

10


Input

5 3
3 4 7 10 3
4 5 5 12 5


Output

25

Note

In the first example Igor should buy item 3 paying 6. But items 1 and 2 he should buy after a week. He will pay 3 and 1 for them. So in total he will pay 6 + 3 + 1 = 10.

In the second example Igor should buy right now items 1, 2, 4 and 5, paying for them 3, 4, 10 and 3, respectively. Item 3 he should buy after a week of discounts, he will pay 5 for it. In total he will spend 3 + 4 + 10 + 3 + 5 = 25.

import java.io.*;
import java.math.BigInteger;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.*;

public class Main {

    static final int INF = Integer.MAX_VALUE;

    static void mergeSort(int[] a, int p, int r) {
        if (p < r) {
            int q = (p + r) / 2;
            mergeSort(a, p, q);
            mergeSort(a, q + 1, r);
            merge(a, p, q, r);
        }
    }

    static void merge(int[] a, int p, int q, int r) {
        int n1 = q - p + 1;
        int n2 = r - q;
        int[] L = new int[n1 + 1], R = new int[n2 + 1];
        // int[] L1 = new int[n1 + 1], R1 = new int[n2 + 1];

        for (int i = 0; i < n1; i++) {
            L[i] = a[p + i];
            //  L1[i] = b[p + i];

        }
        for (int i = 0; i < n2; i++) {
            R[i] = a[q + 1 + i];
            // R1[i] = b[q + 1 + i];

        }
        L[n1] = R[n2] = INF;
        // L1[n1] = R1[n2] = INF;

        for (int k = p, i = 0, j = 0; k <= r; k++) {
            if (L[i] <= R[j]) {

                a[k] = L[i++];
                //  b[k] = L1[i++];

            } else {
                a[k] = R[j++];
                // b[k] = R1[j++];

            }
        }
    }

    static void mergeSort(int[] a, int[] b,int[]c, int p, int r) {
        if (p < r) {
            int q = (p + r) / 2;
            mergeSort(a, b,c, p, q);
            mergeSort(a, b,c, q + 1, r);
            merge(a, b,c, p, q, r);
        }
    }

    static void merge(int[] a, int[] b,int[]c, int p, int q, int r) {
        int n1 = q - p + 1;
        int n2 = r - q;
        int[] L = new int[n1 + 1], R = new int[n2 + 1];
        int[] L1 = new int[n1 + 1], R1 = new int[n2 + 1];
         int[] L2 = new int[n1 + 1], R2 = new int[n2 + 1];
        // int[] L2 = new int[n1 + 1], R2 = new int[n2 + 1];

        for (int i = 0; i < n1; i++) {
            L[i] = a[p + i];
            L1[i] = b[p + i];
             L2[i] = c[p + i];
            // L2[i] = a[p + i];
        }
        for (int i = 0; i < n2; i++) {
            R[i] = a[q + 1 + i];
            R1[i] = b[q + 1 + i];
             R2[i] = c[q + 1 + i];
            //  R2[i] = a[q + 1 + i];
        }
        L[n1] = R[n2] = INF;
        L1[n1] = R1[n2] = INF;
          L2[n1] = R2[n2] = INF;
        int j = 0, k = 0;
        for (int i = p; i <= r; i++) {
            if (L[j] < R[k]) {
                a[i] = L[j];
                b[i] = L1[j];
                 c[i] = L2[j++];
                //j++;
            } else if ((L[j] > R[k])) {
                a[i] = R[k];
                b[i] = R1[k];
                c[i] = R2[k++];
                //k++;
            } else {
                //des
                if (L1[j] > R1[k]) {
                    a[i] = L[j];
                    b[i] = L1[j];
                    c[i] = L2[j++];
                    //j++;
                } else {
                    a[i] = R[k];
                    b[i] = R1[k];
                    c[i] = R2[k++];
                }
            }

        }
    }

    public static int[] sieve(int n) {
        int a[] = new int[n + 1];
        for (int i = 2; i <= n; i++) {
            a[i] = 1;
        }
        for (int i = 2; i <= Math.sqrt(n); i++) {
            if (a[i] == 1) {
                for (int k = 2; i * k <= n; k++) {
                    a[i * k] = 0;
                }
            }
        }
        return a;
    }

    public static long sum(int a) {
        long su = 0;
        while (a > 0) {
            su += (long) a % 10;
            a /= 10;
        }
        return su;
    }

    public static boolean prime(int n) {
        if (n == 1) {
            return true;
        }

        for (int i = 2; i <= Math.sqrt(n); i++) {
            if (n % i == 0) {
                return false;
            }
        }
        return true;
    }

    public static boolean isvowel(char c) {
        if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'y') {
            return true;
        } else {
            return false;
        }
    }

    static long gcd(long a, long b) {
        return b == 0 ? a : gcd(b, a % b);
    }

    static List<Integer> gd(int a, int b) {
        int m = (int) gcd(a, b);
        List<Integer> q = new ArrayList();
        for (int i = 1; i * i <= m; ++i) {
            if (m % i == 0) {
                q.add(i);
                if (i != m / i) {
                    q.add(m / i);
                }
            }
        }
        return q;
    }

    static long sum(long n) {
        return n * (n + 1) / 2;
    }

    static int divisors(int n, int m) {
        if (n - (m + (m * m)) >= 0) {
            return m;
        }
        for (int i = (int) Math.sqrt(m); i >= 1; i--) {
            if (m % i == 0 && n - (m + (m * i)) >= 0) {
                return i;
            }
        }
        return 1;
    }

    static boolean cal(int val, int k, int t) {
        int res = val, p = 1;
        while (val / Math.pow(k, p) > 0) {
            res += val / Math.pow(k, p);
            p++;
        }
        return res >= t;
    }

    static int Last_Ocuu(int[] a, int n, long v) {
        int start = 0, end = n - 1, mid, ans = -1;

        while (start <= end) {
            mid = (start + end) >> 1;
            if (a[mid] < v) {
                ans = mid;
                end = mid - 1;
            } else if (a[mid] >= v) {
                //ans=mid;
                start = mid + 1;
            }

        }
        return ans;
    }

    static long Last_Ocuu(long a, long b, long n) {
        long f = -1000, end = 1000;
        while (f <= end) {
            long mid = (f + end) >> 1;
            if (a * (Math.pow(mid, n)) == b) {
                return mid;
            } else if (a * (Math.pow(mid, n)) > b) {
                end = mid - 1;
            } else {
                f = mid + 1;
            }
        }
        return -1;
    }

    static void print(int a, String s) {

        if (a > 0) {
            //s+='*';
            System.out.println(s);
            print(a - 1, '*' + s);
        } else {
            return;
        }
    }

    static long summtion(int[] a) {
        long s = 0;
        for (int i = 0; i < a.length; i++) {
            s += (long) a[i];
        }
        return s;
    }

    static boolean vv(int i, int j, int n, int m) {
        if (i >= 0 && i < n && j < m && j >= 0) {
            return true;
        }
        return false;
    }

    public static void main(String[] args) throws IOException, ParseException {
        Scannerr in = new Scannerr(System.in);
        PrintWriter or = new PrintWriter(System.out);
        //   BufferedReader b = new BufferedReader(new InputStreamReader(System.in));
        int n = in.nextInt(),k=in.nextInt();
       int[] a= new int[n], b= new int[n];
       int [] c= new int[n];
        for (int i = 0; i < n; i++) a[i]=in.nextInt();
        for (int i = 0; i < n; i++) b[i]=in.nextInt();
          for (int i = 0; i < n; i++) c[i]=a[i]-b[i];
        mergeSort(c,b, a, 0, n-1);
        long ans=0;
        for (int i = 0; i <n; i++) {
            if (k>0) {
                ans+=a[i];
                k--;
            }
            else  {
               
                if (a[i]<=b[i]) {
                    ans+=a[i];
                }
                else ans+=b[i];
            }
        }
        or.print(ans);
        or.flush();

}

static class Scannerr {

    StringTokenizer st;
    BufferedReader br;

    public Scannerr(FileReader fileReader) throws FileNotFoundException {
        br = new BufferedReader(fileReader);
    }

    public Scannerr(InputStream s) throws FileNotFoundException {
        br = new BufferedReader(new InputStreamReader(s));
    }

    public String next() throws IOException {
        while (st == null || !st.hasMoreTokens()) {
            st = new StringTokenizer(br.readLine());
        }
        return st.nextToken();
    }

    public double nextDouble() throws IOException {
        String x = next();
        StringBuilder sb = new StringBuilder("0");
        double res = 0, f = 1;
        boolean dec = false, neg = false;
        int start = 0;
        if (x.charAt(0) == '-') {
            neg = true;
            start++;
        }
        for (int i = start; i < x.length(); i++) {
            if (x.charAt(i) == '.') {
                res = Long.parseLong(sb.toString());
                sb = new StringBuilder("0");
                dec = true;
            } else {
                sb.append(x.charAt(i));
                if (dec) {
                    f *= 10;
                }
            }
        }
        res += Long.parseLong(sb.toString()) / f;
        return res * (neg ? -1 : 1);
    }

    public int nextInt() throws IOException {
        return Integer.parseInt(next());
    }

    public long nextLong() throws IOException {
        return Long.parseLong(next());
    }

    public String nextLine() throws IOException {
        return br.readLine();
    }

    public boolean ready() throws IOException {
        return br.ready();
    }

}



}

class Pair {

    int ind;
    int val;

    //int min;
    public Pair(int n, int p) {
        ind = n;
        val = p;
        // min = m;
    }

}
