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){

        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();
        }
        int[] b = new int[m];
        int[] c = new int[m];
        List<Pair> list = new ArrayList<>();
        for(int i=0; i<m; i++) {
            b[i] = sc.nextInt();
            c[i] = sc.nextInt();
            list.add(new Pair(b[i], c[i]));
        }
        Arrays.sort(a);
        Collections.sort(list);

        int index = 0;

        A: for(Pair p: list) {
            for(int i=0; i<p.b; i++) {
                if(p.c > a[index]) {
                    a[index] = p.c;
                }
                index++;
                if(index >= n) break A;
            }
        }

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

        System.out.println(res);


    }

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

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

}
