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.Comparator;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {

		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		card[] c = new card[200000];
		long sum = 0;

		for(int i = 0; i < 200000; i++) {
			c[i] = new card(0, 0);
		}

		for(int i = 0; i < n; i++) {
			c[i] = new card(sc.nextInt(), 1);
		}

		for(int i = 0; i < m; i++) {
			int num = sc.nextInt();
			int val = sc.nextInt();
			c[n+i] = new card(val, num);
		}

		Arrays.sort(c, new Comparator<card>() {
			public int compare(card c1, card c2) {
				return c2.val - c1.val;
			}
		});

		for(card i : c) {
			for(int j = i.num; j > 0 && n > 0; j--) {
				sum += i.val;
				n--;
			}
		}

		System.out.println(sum);
		sc.close();
	}

	private static class card{
		int val; int num;
		card(int a, int b){
			this.val = a;
			this.num = b;
		}
	}
}