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 myout(Object text){//standard output
		System.out.println(text);
	}
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		//String tmp = sc.next();
		//int tmp = sc.nextInt();
		//Long tmp = sc.nextLong();
      PriorityQueue<Integer> pq = new PriorityQueue<Integer>();
      int N = sc.nextInt();
      int M = sc.nextInt();
      Long output = new Long(0);
      for(int i = 0; i < N; i++){
        pq.add(sc.nextInt());
      }
      
      int[][] bc = new int[M][2];
      for(int i = 0; i < M; i++){
        bc[i][0] = sc.nextInt();
        bc[i][1] = sc.nextInt();
      }
      Arrays.sort(bc,Comparator.comparingInt(o -> o[1]));
      
      for(int i = M - 1; i >= 0; i--){
          for(int j = 0; j < bc[i][0]; j++){
            if(pq.peek() < bc[i][1]){
              pq.poll();
              pq.add(bc[i][1]);
            }else{
              break;
            }
          }
      }
      
      Iterator it = pq.iterator();
      //myout(it);
      while(it.hasNext()){
        int tmp = (Integer)it.next();
        //myout(tmp);
        output = output + tmp;
      }
      myout(output);
	}
}

