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();

		long[] a = new long[n];
		for (int i = 0; i < n; i++) {
			a[i] = sc.nextLong();
		}

		Arrays.sort(a);

		PriorityQueue<long[]> pq = new PriorityQueue<>((x, y) -> -Long.compare(x[1], y[1]));
		while (m-- > 0) {
			pq.offer(new long[]{sc.nextLong(), sc.nextLong()});
		}

		long answer = 0;
		long[] x = pq.poll();
		int count = 0;
		int idx = n - 1;
		while (count < n) {
			if (x != null && a[idx] < x[1] && x[0] > 0) {
				answer += x[1];
				x[0]--;
				if (x[0] == 0) x = pq.poll();
			} else {
				answer += a[idx--];
			}
			count++;
		}

		System.out.println(answer);
	}
}
