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.Optional;
import java.util.Scanner;
import java.util.TreeMap;
import java.util.stream.IntStream;

class Main {
    private static TreeMap<Long, Long> map = new TreeMap<>();
    private static Scanner scanner = new Scanner(System.in);
    public static void main(String... args) {
        int n = scanner.nextInt(), m = scanner.nextInt();
        IntStream.range(0, n).forEach(i -> setMap(1, scanner.nextLong()));
        IntStream.range(0, m)
            .forEach(i -> setMap(scanner.nextInt(), scanner.nextLong()));
        long total = 0, num = 0;
        while ((n -= num) > 0) {
            long lastKey = map.lastKey();
            num = Math.min(map.get(lastKey), n);
            total += num * lastKey;
            map.remove(lastKey);
        }
        System.out.println(total);
    }
    private static void setMap(int num, long value) {
        map.put(value, Optional.ofNullable(map.get(value)).orElse(0l) + num);
    }
}