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();
        TreeMap<Integer, Integer> map = new TreeMap<>();
        for (int i = 0; i < n; i++) {
            int x = sc.nextInt();
            if (map.containsKey(x)) {
                map.put(x, map.get(x) + 1);
            } else {
                map.put(x, 1);
            }
        }
        for (int i = 0; i < m; i++) {
            int count = sc.nextInt();
            int value = sc.nextInt();
            while (count > 0 && value > map.firstKey()) {
                int x = map.firstKey();
                int y = map.get(x);
                if (y <= count) {
                    if (map.containsKey(value)) {
                        map.put(value, y + map.get(value));
                    } else {
                        map.put(value, y);
                    }
                    count -= y;
                    map.remove(x);
                } else {
                    if (map.containsKey(value)) {
                        map.put(value, map.get(value) + count);
                    } else {
                        map.put(value, count);
                    }
                    map.put(x, y - count);
                    count = 0;
                }
            }
        }
        long ans = 0;
        for (Map.Entry<Integer, Integer> entry : map.entrySet()) {
            ans += (long)entry.getKey() * entry.getValue();
        }
        System.out.println(ans);
    }
}