You have N cards. On the i-th card, an integer A_i is written.

For each j = 1, 2, ..., M in this order, you will perform the following operation once:

Operation: Choose at most B_j cards (possibly zero). Replace the integer written on each chosen card with C_j.

Find the maximum possible sum of the integers written on the N cards after the M operations.

Constraints

* All values in input are integers.
* 1 \leq N \leq 10^5
* 1 \leq M \leq 10^5
* 1 \leq A_i, C_i \leq 10^9
* 1 \leq B_i \leq N

Input

Input is given from Standard Input in the following format:


N M
A_1 A_2 ... A_N
B_1 C_1
B_2 C_2
\vdots
B_M C_M


Output

Print the maximum possible sum of the integers written on the N cards after the M operations.

Examples

Input

3 2
5 1 4
2 3
1 5


Output

14


Input

10 3
1 8 5 7 100 4 52 33 13 5
3 10
4 30
1 4


Output

338


Input

3 2
100 100 100
3 99
3 99


Output

300


Input

11 3
1 1 1 1 1 1 1 1 1 1 1
3 1000000000
4 1000000000
3 1000000000


Output

10000000001
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.List;
import java.util.Scanner;
import java.util.AbstractMap.SimpleEntry;

public class Main {

    static final int modnum = 1000000007;

    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int M = sc.nextInt();

        int[] a = new int[N];

        for(int i = 0; i<N;i++){
            a[i] = sc.nextInt();
        }

        Arrays.sort(a);

        // HashMap<Integer,Integer> map = new HashMap<Integer,Integer>();
        ArrayList<SimpleEntry<Integer,Integer>> list = new ArrayList<SimpleEntry<Integer,Integer>>();

        for(int i=0;i<M;i++){
            int b = sc.nextInt();
            int c = sc.nextInt();
            // if(map.containsKey(c))
            //     map.put(c,map.get(c)+b);
            // else
            //     map.put(c,b);
            list.add(new SimpleEntry<Integer,Integer>(c,b));
        }

        Collections.sort(list,Comparator.comparing(SimpleEntry<Integer,Integer>::getKey).reversed());

        int j = 0;
        for(int i=0;i<list.size();i++){
            SimpleEntry<Integer,Integer> pair = list.get(i);
            // System.out.println(pair.toString());
            for(int k=0;k<pair.getValue();k++){
                if(j < N && a[j]<pair.getKey())
                    a[j++]=pair.getKey();
                else
                    break;
            }
        }

        long ans = 0;
        for(int i=0;i<N;i++){
            ans+=a[i];
        }

        // System.out.println(Arrays.toString(a));
        System.out.println(ans);
    }
}