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.*;
import java.io.*;

public class Main
{
	public static void main(String [] Args)
	{
		Scanner in=new Scanner(System.in);
		int n=in.nextInt();
		int m=in.nextInt();
		int [] a=new int [n];
		for(int i=0;i<n;i++)
		{
			a[i]=in.nextInt();
		}
		int [][] b = new int [m][2];
		for(int i=0;i<m;i++)
		{
			b[i][1]=in.nextInt();
			b[i][0]=in.nextInt();
		}
		Arrays.sort(a);
		Arrays.sort(b, (c, d) -> Integer.compare(c[0], d[0]));
		int q=m-1;
		long sum=0;
		for(int i=0;i<n;i++)
		{
			if(b[q][1]==0&&q>0)
			{
				q--;
			}
			if(b[q][0]>a[i]&&b[q][1]>0)
			{
				sum=sum=sum+b[q][0];
				b[q][1]--;
			}
			else
			{
				sum=sum+a[i];
			}
		}
		System.out.println(sum);
	}

}