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) throws Exception {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        
        PriorityQueue<Integer> que = new PriorityQueue<Integer>();
        for (int i = 0; i < n; i++) {
            int num = sc.nextInt();
            que.add(num);
        }
        
        int[][] array = new int[m][2];
        for (int i = 0; i < m; i++) {
            array[i][0] = sc.nextInt();
            array[i][1] = sc.nextInt();
        }
        Arrays.sort(array, (a, b) -> Integer.compare(b[1], a[1]));
        
        for (int i = 0; i < m; i++) {
            int count = array[i][0];
            int val = array[i][1];
            
            boolean ok = true;
            for (int j = 0; j < count; j++) {
                int min = que.peek();
                
                if (min < val) {
                    que.poll();
                    que.add(val);
                } else {
                    ok = false;
                    break;
                }
            }
            
            if (!ok) {
                break;
            }
        }
        
        long ans = 0;
        while (!que.isEmpty()) {
            ans += que.poll();
        }
        System.out.println(ans);
    }
}
