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();
    TreeMap<Integer,Integer> map = new TreeMap<>();
    for(int i=0;i<n;i++){
      int a = sc.nextInt();
      if(map.containsKey(a))map.put(a,map.get(a)+1);
      else map.put(a,1);
    }
    for(int i=0;i<m;i++){
      int b = sc.nextInt();
      int c = sc.nextInt();
      if(map.containsKey(c))map.put(c,map.get(c)+b);
      else map.put(c,b);
    }
    long result = 0;
    int res = n;
    while(true){
      Map.Entry<Integer,Integer> entry = map.pollLastEntry();
      long key = entry.getKey();
      long value = entry.getValue();
      if(res>value){
        res-=value;
        result+=value*key;
      }else{
        result+=res*key;
        break;
      }
    }
    System.out.println(result);
  }
}