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.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.Arrays;
import java.util.Comparator;
import java.util.PriorityQueue;
public class Main {
  public static void main(String[] args) {
    Main m = new Main();
    m.run();
  }
  private void run() {
    try (BufferedReader br = new BufferedReader(new InputStreamReader(System.in));) {
      String[] s = br.readLine().split("\\s+");
      int n = Integer.parseInt(s[0]);
      int m = Integer.parseInt(s[1]);
      int[] a = Arrays.stream(br.readLine().split("\\s+"))
        .mapToInt(Integer::parseInt).toArray();
      PriorityQueue<Integer> pq = new PriorityQueue<>();
      PriorityQueue<Operation> op = new PriorityQueue<>(Comparator.reverseOrder());
      for (int i=0;i<n;i++) pq.offer(a[i]);
      for (int i=0;i<m;i++) {
        s = br.readLine().split("\\s+");
        int b = Integer.parseInt(s[0]);
        int c = Integer.parseInt(s[1]);
        op.offer(new Operation(b,c));
      }
      for (int i=0;i<m;i++) {
        Operation o = op.poll();
        for (int j=0;j<o.b;j++) {
          int d = pq.peek();
          if (d >= o.c) break;
          d = pq.poll();
          pq.offer(o.c);
        }
      }
      long sum = 0L;
      for (int i=0;i<n;i++) sum += (long)pq.poll();
      System.out.println(sum);
    } catch (IOException e) {
      e.printStackTrace();
    }
  }
  private class Operation implements Comparable<Operation> {
    int b,c;
    Operation(int b,int c) {
      this.b = b;
      this.c = c;
    }
    @Override
    public int compareTo(Operation other) {
      if (c == other.c) return Integer.compare(b,other.b);
      return Integer.compare(c,other.c);
    }
  }
}