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 scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int m = scanner.nextInt();
        int[] a = new int[n];
        int[][] bc = new int[m][2];
        long sum = 0;

        for (int i = 0; i < n; i++) {
            a[i] = scanner.nextInt();
        }

        Arrays.sort(a);
        for (int i = 0; i < m; i++) {
            bc[i][0] = scanner.nextInt();
            bc[i][1] = scanner.nextInt();
        }

        Arrays.sort(bc, (t, b) -> Integer.compare(t[1], b[1]));

        int k = 0;
        for (int i = m-1; i >= 0; i--) {
            if(k>a.length-1){
                break;
            }
            if(a[k] >= bc[i][1]){
                break;
            }
            for (int j = 0; j < bc[i][0]; j++) {
                if (a[k] < bc[i][1]) {

                    a[k++] = bc[i][1];
                    if(k>a.length-1){
                        break;
                    }
                } else {
                    break;
                }
            }
        }
        for(int i = 0 ; i < n ; i++){
            sum+=a[i];
        }
        System.out.println(sum);
    }

}
