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.Arrays;
import java.util.PriorityQueue;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int n = in.nextInt();
		int m = in.nextInt();

		PriorityQueue<Integer> a = new PriorityQueue<>();
		for ( int i = 0; i < n; i++ ) {
			a.add(in.nextInt());
		}

		int[][] bc = new int[m][2];
		for ( int i = 0; i < m; i++ ) {
			bc[i][0] = in.nextInt();
			bc[i][1] = in.nextInt();
		}

		Arrays.sort(bc, (o1, o2) -> o2[1] - o1[1]);

		for ( int i = 0; i < m; i++ ) {
			while ( !a.isEmpty() && a.peek() < bc[i][1] && 0 < bc[i][0] ) {
				a.poll();
				a.add(bc[i][1]);
				bc[i][0]--;
			}
		}

		long ans = 0L;
		for ( Integer i : a ) {
			ans += i;
		}
		System.out.println(ans);
		in.close();
	}
}