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 A[]=new int[N];
		for(int i=0;i<N;i++) A[i]=sc.nextInt();
		int D[][] = new int[M][2];
		for(int i=0;i<M;i++) {
			D[i][0]=sc.nextInt();//B
			D[i][1]=sc.nextInt();//C
		}
		sc.close();
		Queue<Integer> pq = new PriorityQueue<Integer>();
		for(int i=0;i<N;i++)pq.offer(A[i]);
		//reverse sort D by C
		Arrays.sort(D,(d1,d2)->d2[1]-d1[1]);
		
		boolean fin = false;
		for(int i=0;i<M;i++) {
			int tB = D[i][0];
			int tC = D[i][1];
			for(int j=0;j<tB;j++) {
				if(pq.peek()<tC) {
					pq.poll();
					pq.offer(tC);
				}else {
					fin = true;
					break;
				}
			}
			if(fin)break;
		}
		long ans = 0;
		while(!pq.isEmpty()) {
			ans += pq.poll();
		}
		System.out.println(ans);
	}
}