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.util.*;
import java.math.*;
import java.io.*;
public class Luck{
	public static InputReader sc;
    public static PrintWriter out;
    public static final long MOD = (long) (1e9 + 7);
    public static void main(String[] args){
    	sc=new InputReader(System.in);	
    	out=new PrintWriter(System.out);
    	int n=sc.nextInt();
    	int k=sc.nextInt();
    	int count=0;
    	ArrayList<Pair> l=new ArrayList<Pair>(); 
    	int[] A=new int[n];
    	for(int i=0;i<n;i++){
    		A[i]=sc.nextInt();
    	}
    	int ans=0;
    	int[] B=new int[n];
    	int sum=0;
    	for(int i=0;i<n;i++){
    		B[i]=sc.nextInt();
    		sum+=B[i];
    		if(A[i]-B[i]<=0){
    			ans+=A[i];
    			sum-=B[i];
    			count+=1;
    		}
    		else{
    			l.add(new Pair(A[i]-B[i],i));
    		}
    	}
    	if(count>=k){
    		out.println(ans+sum);
    	}
    	else{
    		Collections.sort(l, Pair.Val);
    		int i=0;
    		while(count<k){
    			count+=1;
    			int index=l.get(i).val;
    			i+=1;
    			ans+=A[index];
    			sum-=B[index];
    		}
    		out.println(ans+sum);
    	}
    	out.close();
    }
  
    static class Pair{
    	int profit;
    	int val;
    	Pair(){
    		this.profit=-1;
    		this.val=-1;
    	}
    	Pair(int profit,int val){
    		this.profit=profit;
    		this.val=val;
    	}
    	public static Comparator<Pair> Val=new Comparator<Pair>(){
    		public int compare(Pair p1,Pair p2){
    			return (int)p1.profit-(int)p2.profit;
    		}
    	};
    	public int hashCode() {
    		final int prime = 31;
    		int result = 1;
    		result = prime * result + profit;
    		result = prime * result + val;
    		return result;
    	}
    	public boolean equals(Object obj){
    		if (this == obj)
    	        return true;
    	    if (!(obj instanceof Pair)) {
    	        return false;
    	    }
    	 
    	    Pair p = (Pair) obj;
    	    if(p.profit!=this.profit){
    	    	return false;
    	    }
    	    else if(p.val!=p.val){
    	    	return false;
    	    }
    	    return true;
    	}
    }
//    static int val;
//    static class DisjointSet{
//    	int n;
//    	int[] par;
//    	int[] rank;
//    	DisjointSet(int n){
//    		this.n=n;
//    		this.par=new int[n];
//    		this.rank=new int[n];
//    		makeSet();
//    	}
//    	void makeSet(){
//    		for(int i=1;i<n;i++){
//    			par[i]=i;
//    			rank[i]=1;
//    		}
//    	}
//    	void union(int x,int y){
//    		int parX=parent(x);
//    		int parY=parent(y);
//    		if(parX!=parY){
//    			if(rank[parX]>=rank[parY]){
//    				rank[parX]+=rank[parY];
//    				rank[parY]=0;
//    				par[parY]=parX;
//    			}
//    			else{
//    				rank[parY]+=rank[parX];
//    				rank[parX]=0;
//    				par[parX]=parY;
//    			}
//    			val-=1;
//    		}
//    	}
//    	int parent(int c){
//    		int i=c;
//    		while(i!=par[i]){
//    			i=par[i];
//    		}
//    		return i;
//    	}
//    }
    static int gcd(int a,int b){
    	if(b==0){
    		return a;
    	}
    	return gcd(b,a%b);
    	
    }
    static int lcm(int a,int b){
    	int g;
    	if(a<b){
    		g=gcd(b,a);
    	}
    	else{
    		g=gcd(a,b);
    	}
    	return (a*b)/g;
    }
    static long bigmod ( long a, long p, long m ) {
        long res = 1 % m, x = a % m;
        while ( p>0 ) {
            if ( (p & 1)==1 ) res = ( res * x ) % m;
            x = ( x * x ) % m; p >>= 1;
        }
        return res;
    }
    static boolean isPrime(int n){
    	 if (n == 2)
    	        return true;
    	    for (long i = 2; i * i <= n; i++) {
    	        if (n % i == 0)
    	            return false;
    	    }
    	    return true;
    }
    
    static void shuffle(int[] A){
    	for(int i=A.length-1;i>0;i--){
    		int j=(int)(Math.random()*(i+1));
    		int temp=A[j];
    		A[j]=A[i];
    		A[i]=temp;
    	}
    }
    
	public static class Node implements Comparable<Node>{
	    int u;
	    int v;
	    public Node(){
	    	;
	    }
	    public Node (int u, int v) {
	    	this.u = u;
	        this.v = v;
	    }
	    
	    public void print() {
	        out.println(v + " " + u + " ");
	    }
	   
	    public int compareTo(Node n1){
	    	return this.u-n1.u;
	    }
	}
	public static long pow(long base,long exp,long mod){
		if(exp==0){
			return 1;
		}
		if(exp==1){
			return base;
		}
		long temp=exp/2;
		long val=pow(base,temp,mod);
		long result=val*val;
		result=(result%mod);
		long AND=exp&1;
		if(AND==1){
			result*=base;
			result=(result%mod);
		}
		return result;
	}
	public static BigInteger pow(BigInteger base, BigInteger exp) {
	    if(exp.equals(new BigInteger(String.valueOf(0)))){
	        return new BigInteger(String.valueOf(1));
	    }    
	    if(exp.equals(new BigInteger(String.valueOf(1))))
	        return base;
	    BigInteger temp=exp.divide(new BigInteger(String.valueOf(2)));
	    BigInteger val = pow(base, temp);
	    BigInteger result = val.multiply(val);
	    result=result.remainder(new BigInteger(String.valueOf(MOD)));
	    BigInteger AND=exp.and(new BigInteger(String.valueOf(1)));
	    if(AND.equals(new BigInteger(String.valueOf(1)))){
	        result = result.multiply(base);
	        result=result.remainder(new BigInteger(String.valueOf(MOD)));
	    }    
	    return result;
	}
	    
	static class InputReader {

	    private InputStream stream;
	    private byte[] buf = new byte[8192];
	    private int curChar, snumChars;
	    private SpaceCharFilter filter;

	    public InputReader(InputStream stream) {
	        this.stream = stream;
	    }

	    public int snext() {
	        if (snumChars == -1)
	            throw new InputMismatchException();
	        if (curChar >= snumChars) {
	            curChar = 0;
	            try {
	                snumChars = stream.read(buf);
	            } catch (IOException e) {
	                throw new InputMismatchException();
	            }
	            if (snumChars <= 0)
	                return -1;
	        }
	        return buf[curChar++];
	    }

	    public int nextInt() {
	        int c = snext();
	        while (isSpaceChar(c))
	            c = snext();
	        int sgn = 1;
	        if (c == '-') {
	            sgn = -1;
	            c = snext();
	        }
	        int res = 0;
	        do {
	            if (c < '0' || c > '9')
	                throw new InputMismatchException();
	            res *= 10;
	            res += c - '0';
	            c = snext();
	        } while (!isSpaceChar(c));
	        return res * sgn;
	    }

	    public long nextLong() {
	        int c = snext();
	        while (isSpaceChar(c))
	            c = snext();
	        int sgn = 1;
	        if (c == '-') {
	            sgn = -1;
	            c = snext();
	        }
	        long res = 0;
	        do {
	            if (c < '0' || c > '9')
	                throw new InputMismatchException();
	            res *= 10;
	            res += c - '0';
	            c = snext();
	        } while (!isSpaceChar(c));
	        return res * sgn;
	    }

	    public int[] nextIntArray(int n) {
	        int a[] = new int[n];
	        for (int i = 0; i < n; i++)
	            a[i] = nextInt();
	        return a;
	    }

	    public String readString() {
	        int c = snext();
	        while (isSpaceChar(c))
	            c = snext();
	        StringBuilder res = new StringBuilder();
	        do {
	            res.appendCodePoint(c);
	            c = snext();
	        } while (!isSpaceChar(c));
	        return res.toString();
	    }

	    public boolean isSpaceChar(int c) {
	        if (filter != null)
	            return filter.isSpaceChar(c);
	        return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
	    }

	    public interface SpaceCharFilter {
	        public boolean isSpaceChar(int ch);
	    }
	}

}

