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.Comparator;
import java.util.Map;
import java.util.Scanner;
import java.util.TreeMap;

public class Main {
	public static void main(String[] args) {
		try (Scanner s = new Scanner(System.in)) {
			final int N = s.nextInt();
			final int M = s.nextInt();

			Map<Integer, Integer> map = new TreeMap<Integer, Integer>(Comparator.reverseOrder());
			for (int i = 0; i < N; i++) {
				Integer a = s.nextInt();
				if (map.containsKey(a)) {
					map.put(a, map.get(a).intValue() + 1);
				} else {
					map.put(a, 1);
				}
			}

			for (int i = 0; i < M; i++) {
				int b = s.nextInt();
				Integer c = s.nextInt();

				if (map.containsKey(c)) {
					map.put(c, map.get(c).intValue() + b);
				} else {
					map.put(c, b);
				}
			}

			long sum = 0;
			int n = N;
			for (Map.Entry<Integer, Integer> e : map.entrySet()) {
				long w = Math.min(n, e.getValue());
				sum += e.getKey() * w;
				n -= w;
				if (n < 1) {
					break;
				}
			}
			System.out.println(sum);
		}
	}
}
