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.Scanner;
import java.util.Arrays;
import java.util.TreeMap;
public class Main{
	public static void main(String[] args){
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		long[] a = new long[n];
		TreeMap<Long,Integer> map=new TreeMap<>();
		for(int i=0; i<n; i++){
			a[i]= sc.nextLong();
		}
		Arrays.sort(a);
		for(int i=0; i<m; i++){
			int b = sc.nextInt();
			long c = -sc.nextLong();
			if(map.containsKey(c)){
				map.put(c,b+map.get(c));
			}else{
				map.put(c,b);
			}
		}
		long ans=0;
		int i=0;
		for(long k:map.keySet()){
			int count=map.get(k);
			for(;i<n; i++){
				if(a[i]<-k){
					count--;
					a[i]=-k;
				}
				if(count==0){
					break;
				}
			}
		}
		for(i=0; i<n; i++){
			ans+=a[i];
		}
		System.out.println(ans);
	}
}
