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.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		// TODO 自動生成されたメソッド・スタブ
		Scanner sc = new Scanner(System.in);

		int n = sc.nextInt();
		int m = sc.nextInt();

		int cards[] = new int[n];
		for(int i = 0; i < n; i++){
			cards[i] = sc.nextInt();
		}

		Arrays.sort(cards);

		ArrayList<Numbers> list = new ArrayList<Numbers>();

		int count = 0;
		for(int i = 0; i < n; i++){
			if(i >= 1 && cards[i] != cards[i - 1]){
				list.add(new Numbers(cards[i - 1], count));
				count = 1;
			}
			else {
				count++;

			}
			if(i == n - 1){
				list.add(new Numbers(cards[i], count));
			}
		}

//		Numbers changes[] = new Numbers[m];
		for(int i = 0; i < m; i++){
			int b = sc.nextInt();
			int c = sc.nextInt();

//			changes[i] = new Numbers(c, b);
			list.add(new Numbers(c, b));
		}
//		Arrays.sort(changes);
		Collections.sort(list);

		long sum = 0;
		int remain = n;

		for(int i = 0; i < list.size(); i++){
//			System.out.println("value "+list.get(i).value+" count "+list.get(i).num);

			Numbers tmpNum = list.get(i);

			int use = Math.min(remain, tmpNum.num);

			sum += (long)use*tmpNum.value;

			remain -= use;

			if(remain == 0){
				break;
			}
		}

		System.out.println(sum);
	}

}

class Numbers implements Comparable<Numbers>{
	int value;
	int num;

	Numbers(int value, int num){
		this.value = value;
		this.num = num;
	}

	@Override
	public int compareTo(Numbers c1) {
		// TODO 自動生成されたメソッド・スタブ
		return c1.value - this.value;
	}


}
