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

public class Main {

	public static void main(String[] args) {
		try (Scanner scanner = new Scanner(System.in)) {
			int n = scanner.nextInt(), m = scanner.nextInt();
			SortedMap<Integer, Integer> map = new TreeMap<>();
			IntStream.range(0, n).forEach(i -> {
				int a = scanner.nextInt();
				map.put(a, map.getOrDefault(a, 0) + 1);
			});
			IntStream.range(0, m).forEach(i -> {
				int b = scanner.nextInt(), c = scanner.nextInt();
				int count = 0;
				while ((b > 0) && (map.firstKey() < c)) {
					int exists = map.get(map.firstKey());
					if (exists > b) {
						count += b;
						map.put(map.firstKey(), exists - b);
						map.put(c, map.getOrDefault(c, 0) + b);
						b = 0;
					} else {
						count += exists;
						map.put(c, map.getOrDefault(c, 0) + exists);
						map.remove(map.firstKey());
						b -= exists;
					}
				}
			});
			System.out.println(
					map.entrySet().stream().mapToLong(entry -> entry.getKey() * (long) entry.getValue()).sum());
		}
	}
}
