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.Scanner;

public class Main {
    void run() {
        Scanner sc = new Scanner(System.in);

        int n = sc.nextInt(), m = sc.nextInt();
        PriorityQueue<P> q = new PriorityQueue<>();

        for (int i = 0; i < n; i++) q.add(new P(1, sc.nextInt()));

        for (int i = 0; i < m; i++) q.add(new P(sc.nextInt(), sc.nextInt()));

        long ans = 0;

        while (n > 0) {
            P cur = q.remove();

            if (n > cur.b) {
                n -= cur.b;
                ans += 1L * cur.b * cur.c;
            } else {
                ans += 1L * n * cur.c;
                n = 0;
            }
        }
        System.out.println(ans);
    }

    class P implements Comparable<P> {
        int b, c;
        P(int b, int c) {
            this.b = b;
            this.c = c;
        }

        @Override
        public int compareTo(P o) {
            return o.c - c;
        }
    }

    void debug(Object...os) {
        System.err.println(Arrays.deepToString(os));
    }

    public static void main(String[] args) {
        new Main().run();
    }

}
