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.*;

class Step implements Comparable<Step>{
  int b;
  long c;
  public Step( int d, long e ){
    b = d;
    c = e;
  }

  @Override
  public int compareTo( Step p ){
    if(this.c - p.c > 0) return 1;
    else if(this.c - p.c < 0) return -1;
    else return 0;
    //return (int)(this.c - p.c);
  }
}

public class Main{

    public static void main(String args[]){

        // スキャナーの宣言
        Scanner sc = new Scanner(System.in);
        // 整数の入力
		int n = sc.nextInt();
        // スペース区切りの整数の入力
        int m = sc.nextInt();
        //配列の宣言
        //int[] num = new int[n];
        long[] num = new long[n];

        for(int i = 0; i < n; i++){
            //num[i] = sc.nextInt();
            num[i] = sc.nextLong();
        }

        Arrays.sort(num);

        List<Step> list = new ArrayList<>();

        int b;
        long c;
        for(int i = 0; i < m; i++){
            b = sc.nextInt();
            c = sc.nextLong();
            list.add(new Step(b, c));
        }
        Collections.sort(list, Comparator.reverseOrder());
        //System.out.println(list);
        int k = 0, l;
        for(int i = 0; i < list.size(); i++){
            b = list.get(i).b;
            c = list.get(i).c;
            l = 0;
            //if(num[k] >= c) break;
            while(true){
                if(l < b && k < n && num[k] < c){
                    num[k] = c;
                    k++;
                    l++;
                }else{
                    break;
                }
            }
            if(k >= n) break;
            /*for(int j = 0; j < b; j++){
                if(num[j] < c){
                    num[j] = c;
                }else{
                    Arrays.sort(num);
                    break;
                }
            }
            if(num[b-1] == c) Arrays.sort(num);*/
        }

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

        // 出力
        System.out.println(ans);

    }

}