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 Main{
  public static void main(String args[]){
    Scanner sc = new Scanner(System.in);
    int n=sc.nextInt();
    int m=sc.nextInt();
    int[] a=new int[n];
    for(int i=0;i<n;i++){
      a[i]=sc.nextInt();
    }
    Arrays.sort(a);
//    System.out.println(Arrays.toString(a));
    Pair[] ps=new Pair[m];
    for(int i=0;i<m;i++){
      ps[i]=new Pair(sc.nextInt(),sc.nextInt());
    }
    Arrays.sort(ps,(s1,s2)->s2.alte-s1.alte);
//    System.out.println(Arrays.toString(ps));
    int idx=0;
    for(int i=0;i<m;i++){
      while(ps[i].many>0){
        if(idx>=a.length){
          break;
        }
        if(a[idx]>=ps[i].alte){
          break;
        }else{
          a[idx]=ps[i].alte;
          ps[i].many--;
          idx++;
        }
      }
    }
//    System.out.println(Arrays.toString(a));
    long sum=0;
    for(int i=0;i<a.length;i++){
      sum+=a[i];
    }
    System.out.println(sum);
  }
  static class Pair{
    int many;
    int alte;
    Pair(int b,int c){
      many=b;
      alte=c;
    }
    public String toString(){
      return String.valueOf(many)+":"+String.valueOf(alte);
    }
  }
}