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;

class pair{
	int a;
	int b;
	pair(int x,int y)
	{
		a=x;
		b=y;
	}
}

class compare implements Comparator<pair>{

	@Override
	public int compare(pair o1, pair o2) {
		if(o1.b>o2.b)
		{
			return -1;
			
		}
		else if(o1.b<o2.b)
		{
			return 1;
		}else
		{
			return 0;
		}
	}
	
}
public class Main {

	public static void main(String args[])
	{
		Scanner scan=new Scanner(System.in);
		int n=scan.nextInt();
		int m=scan.nextInt();
		int ar[]=new int[n];
		for(int i=0;i<n;i++)
		{
			ar[i]=scan.nextInt();
		}
		pair cng[]=new pair[m];
		
		for(int i=0;i<m;i++)
		{
		cng[i]=new pair(scan.nextInt(),scan.nextInt());	
		}
		Arrays.parallelSort(cng,new compare());
		//try to change the smallest values of orginal arrays with the biggest values form array m
		Arrays.parallelSort(ar);
		int x=0;
		int y=0;
		while(x<m)
		{
			int times=cng[x].a;
			int val=cng[x].b;
			while(times>0 && y<n&&ar[y]<val)
			{
				ar[y]=val;
				y++;
				times--;
			}
			x++;
		}
		long sum=0;
		for(int i=0;i<n;i++)
		{
			sum+=ar[i];
		}
		System.out.println(sum);
	}
	
}
