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[] arr = new int[n];

        long ans = 0;

        for (int i=0; i<n; i++) arr[i] = sc.nextInt();
        Arrays.sort(arr);

        int[] b = new int[m];
        Pair[] c = new Pair[m];
//        int[] c = new int[m];

        for (int i=0; i<m; i++){
            int bCnt = sc.nextInt();
            int tmp = sc.nextInt();
            c[i] = new Pair(tmp, bCnt);
        }

        Arrays.sort(c);

        int idx = 0;

        for (int i=0; i<m; i++){
            int cnt = c[i].cnt;
            int change = c[i].change;
            while (idx<n && arr[idx]<change && cnt>0){
                arr[idx] = change;
                idx++;
                cnt--;
            }
        }

        for (int i=0; i<n; i++){
            ans += arr[i];
        }

        System.out.println(ans);


    }

    public static class Pair implements Comparable<Pair>{
        int change;
        int cnt;
        Pair(int c, int i){
            this.change = c;
            this.cnt = i;
        }

        public int compareTo(Pair pair){
            if (this.change<pair.change) return 1;
            if (this.change>pair.change) return -1;
            return 0;
        }
    }
}

