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();
    List<Integer> A = new ArrayList<>();
    int[][] BC = new int[M][2];

    for (int i = 0; i < N; i++) {
      A.add(sc.nextInt());
    }

    for (int i = 0; i < M; i++) {
      int B_ = sc.nextInt();
      int C_ = sc.nextInt();
      BC[i][0] = B_;
      BC[i][1] = C_;
    }

    sc.close();

    Arrays.sort(BC, (a,b) -> Integer.compare(b[1],a[1]));

    int count = 0;

    roop: for (int i = 0; i < M; i++) {
      for (int j = 0; j < BC[i][0]; j++) {
        A.add(BC[i][1]);
        count++;
        if (N <= count){
          break roop;
        }
      }
    }

    Collections.sort(A, Comparator.reverseOrder());
    
    long sum = 0;

    for (int i = 0; i < N; i++) {
      sum += A.get(i);
    }

    System.out.println(sum);

  }

}