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.Arrays;
import java.util.PriorityQueue;
import java.util.Queue;
import java.util.Scanner;

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

            Queue<Long> aQueue = new PriorityQueue<>(N);
            for (int i = 0; i < N; i++) {
                aQueue.add(sc.nextLong());
            }

            long[][] bcList = new long[M][2];
            for (int i = 0; i < M; i++) {
                bcList[i][0] = sc.nextInt();
                bcList[i][1] = sc.nextLong();
            }

            Arrays.sort(bcList, (a, b) -> Long.compare(a[1], b[1]));

            A: for (int i = bcList.length - 1; i >= 0; i--) {
                long[] bc = bcList[i];
                long b = bc[0];
                long c = bc[1];

                for (int j = 0; j < b; j++) {
                    Long a = aQueue.poll();
                    if (a < c) {
                        aQueue.add(c);
                    } else {
                        aQueue.add(a);
                        break A;
                    }
                }
            }

            System.out.println(aQueue.stream().reduce((current, value) -> current + value).get());
        }
    }

}