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();

        ArrayList<Long> bc = new ArrayList<>();

        for (int i=0; i<N; i++){
            bc.add(sc.nextLong());
        }

        long[][] tmpBC = new long[M][2];

        for (int i=0; i < M; i++){
            tmpBC[i][0] = sc.nextInt();
            tmpBC[i][1] = sc.nextLong();
        }
        sc.close();

        Arrays.sort(tmpBC, Comparator.comparing((long[] arr) -> arr[1]).reversed());

//        for (int z=0; z<M; z++){
//            System.out.println("tmpB["+z+"]:"+ tmpBC[z][0]+" tmpC["+z+"]:"+ tmpBC[z][1]);
//        }

        int count=0;
        END: for (int i=0; i<M; i++){
            for (int j=0; j<tmpBC[i][0]; j++){
                bc.add(tmpBC[i][1]);
                count++;
                if(count >= N){
                    break END;
                }
            }
        }

        Collections.sort(bc, Comparator.reverseOrder());

        long result=0;
        for (int i=0; i<N; i++){
            result += bc.get(i);
        }

        System .out.println(result);

    }
}