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.*;

public class Main {

    public static void main(String[] args) {
        // write your code here
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt();
        int m = sc.nextInt();
        PriorityQueue<Integer> a = new PriorityQueue<>(Comparator.reverseOrder());

        for (int i = 0; i < n; i++) {
            a.add(sc.nextInt());
        }

        ArrayList<Swap> list = new ArrayList<>();

        for (int i = 0; i < m; i++) {
            list.add(new Swap(sc.nextInt(), sc.nextInt()));
        }

        list.sort((sa, sb) -> sb.value - sa.value);

        int count = 0;
        for (Swap s : list) {
            int add = Math.min(n - count, s.count);
            for (int i = 0; i < add; i++) {
                a.add(s.value);
            }
            count += add;
            if (count == n) {
                break;
            }
        }

        long ans = 0;

        for (int i = 0; i < n; i++) {
            ans += a.poll();
        }

        System.out.println(ans);
    }

    private static class Swap {
        private int count;
        private int value;

        public Swap(int count, int value) {
            this.count = count;
            this.value = value;
        }
    }
}
