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) {
//        long startTime = System.currentTimeMillis();
        Scanner scanner = new Scanner(System.in);
        int N = scanner.nextInt();
        int M = scanner.nextInt();
        List<Long> A = new ArrayList<>();
        for (int i = 0; i < N; i++) {
            A.add(scanner.nextLong());
        }
        List<Map.Entry<Integer, Long>> BC = new ArrayList<>();
        for (int i = 0; i < M; i++) {
            Map.Entry<Integer, Long> entry =
                    new AbstractMap.SimpleEntry<>(scanner.nextInt(), scanner.nextLong());
            BC.add(entry);
        }
        scanner.close();

        // A sort
        Collections.sort(A);

        // BC sort
        Collections.sort(BC, (o1, o2) -> o2.getValue().compareTo(o1.getValue()));

        // B count
        long bCount = 0;
        // B C
        List<Long> replaceList = new ArrayList<>();
        for (Map.Entry<Integer, Long> entry : BC) {
            int b = entry.getKey();
            long c = entry.getValue();
            for (int j = 0; j < b; j++) {
                replaceList.add(c);
                bCount++;
                if (replaceList.size() == N) {
                    break;
                }
            }
            if (replaceList.size() == N) {
                break;
            }
        }
        Collections.sort(replaceList);
        Collections.reverse(replaceList);

//        System.out.println(BC);

        for (int i = 0; i < bCount; i++) {
            long a = A.get(i);
            long bc = replaceList.get(i);
            if (a < bc) {
                A.set(i, bc);
//                System.out.println(A);
            } else {
                break;
            }
        }

        long sum = 0;
        for (long l : A) {
            sum += l;
        }

        System.out.println(sum);

//        System.out.println(System.currentTimeMillis() - startTime);
    }


}
