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.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.PriorityQueue;
import java.util.Scanner;
import java.util.Set;

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();
		}

		Pair[] p = new Pair[m];
		for( int i=0 ; i<m ; i++ ) {
			p[i] = new Pair(sc.nextInt(),sc.nextInt());
		}

		Arrays.sort(a);
		Arrays.sort(p);

		int s=0;
		for( int i=0 ; i< m ; i++) {
			int b = p[i].r;
			int c = p[i].l;
			
			while( b>0 && s<n && a[s] < c ) {
				a[s] = c;
				s++;
				b--;
			}
		}
		
		long ans = 0;
		for( int i=0 ; i< n ; i++) {
			ans += a[i];
		}
		System.out.println(ans);
		
	}

	public static class Pair implements Comparable<Pair>{
		int r = 0;
		int l = 0;
		
		public Pair(int weight, int limit) {
			super();
			this.r = weight;
			this.l = limit;
		}

		@Override
		public int compareTo(Pair o) {
			if(false)
				// ASC
				return (l - o.l);
			else
				// DESC
				return -(l - o.l);
		}
	
	}
}

