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) {
		Main main = new Main();
		main.run();
	}

	class Pair implements Comparable<Pair>{
		int x;
		int y;
		Pair(int x, int y){
			this.x=x;
			this.y=y;
		}
		@Override
		public int compareTo(Pair o) {
			return Integer.compare(this.y, o.y);
		}

	}
	public void run() {
		Scanner sc = new Scanner(System.in);

		int N=sc.nextInt();
		int M=sc.nextInt();
		ArrayList<Integer> A = new ArrayList<>();
		long sum = 0;
		for(int i=0; i<N; i++) {
			A.add(sc.nextInt());
			sum += A.get(i);
		}

		ArrayList<Pair> BC = new ArrayList<>();
		for(int i=0; i<M; i++) {
			int b=sc.nextInt();
			int c=sc.nextInt();
			Pair p = new Pair(b,c);
			BC.add(p);
		}

		Collections.sort(A);
		Collections.sort(BC, Collections.reverseOrder());

		ArrayList<Integer> D = new ArrayList<>();
		for(int i=0; i<BC.size(); i++) {
			Pair p = BC.get(i);
			for(int j=0; j<p.x; j++) {
				D.add(p.y);
				if(D.size()>=N) {
					break;
				}
			}
		}

		int j=0;
		for(int i=0; i<D.size(); i++) {
			if(j<A.size() && A.get(j)<D.get(i)) {
				sum += D.get(i)-A.get(j);
				j++;
			}else {
				break;
			}
		}
		System.out.println(sum);
		sc.close();
	}
}
