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);
		// 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();
      int a[] = new int[n];
      Map<Integer, Integer> map = new HashMap<>();
      int b=0;
      Integer c[] = new Integer[m];
      for(int i=0;i<n;i++){
        a[i] = sc.nextInt();
	   }
      Arrays.sort(a);
       for(int j=0;j<m;j++){
        b = sc.nextInt();
        c[j] = sc.nextInt();
        if(map.containsKey(c[j])){
          map.put(c[j], map.get(c[j])+b);
        }else{
          map.put(c[j],b);
        }
	   }
      Arrays.sort(c, Collections.reverseOrder());
      int k = 0;
      int kk = 0;
      int before = 0;
      for(Integer max:c){
        for(kk=0;max!=before&&k<n && kk<map.get(max)&&max>a[k];kk++){
          a[k]=max;
          k++;
        }
        before = max;
      }
      long sum =0;
      for(int ap:a){
        sum+=ap;
      }
      System.out.println(sum);
    }
}