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();
    long[] a = new long[n];
    long sum = 0;
    for(int i = 0; i < n; i++) {
      a[i] = sc.nextLong();
      sum += a[i];
    }
    Arrays.sort(a);
    ArrayList<Long> c = new ArrayList<Long>();
    HashMap<Long, Integer> map = new HashMap<Long, Integer>();
    for(int i = 0; i < m; i++) {
      int b = sc.nextInt();
      long cc = sc.nextLong();
   //   if(!(c.contains(cc))) c.add(cc);
      c.add(cc);
      if(map.containsKey(cc)) {
        map.put(cc, map.get(cc) + b);
      } else {
        map.put(cc, b);
      }
    }
    Collections.sort(c);
    long[] d = new long[n];
    int p = 0;
    long r = 0;
    for(int i = c.size() - 1; i >= 0; i--) {
      if(p >= n) break;
      long s = c.get(i);
      if(r == s) continue; 
      int t = map.get(s);
      r = s;
      for(int j = 0; j < t; j++) {
        if(p >= n) break;
        d[p] = s;
        p++;
      }
    }
    for(int i = 0; i < n; i++) {
      if(d[i] > a[i]) {
        sum += (d[i] - a[i]);
      } else {
        break;
      }
    }
    System.out.println(sum);
  }
}
