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();
		int[] arr = new int[n];
		for (int i = 0; i < n; i++) {
			arr[i] = sc.nextInt();
		}
		Arrays.sort(arr);
		Change[] base = new Change[m];
		for (int i = 0; i < m; i++) {
			base[i] = new Change(sc.nextInt(), sc.nextInt());
		}
		Arrays.sort(base, new Comparator<Change>() {
		public int compare(Change c1, Change c2) {
			return c2.c - c1.c;
		}
		});
		int[] rel = new int[n];
		int idx = 0;
		for (int i = 0; idx < n && i < m; i++) {
			for (int j = 0; idx < n && j < base[i].b; j++) {
				rel[idx] = base[i].c;
				idx++;
			}
		}
		long total = 0;
		for (int i = 0; i < n; i++) {
			total += Math.max(arr[i], rel[i]);
		}
		System.out.print(total);
	}
	
	static class Change {
		int b;
		int c;
		public Change(int b, int c) {
			this.b = b;
			this.c = c;
		}
	}
}
