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();
		PriorityQueue<Long> pq = new PriorityQueue<>();
		for(int i=0; i<n; i++){
			pq.add(sc.nextLong()); 
		}
		Map<Long, Integer> map = new TreeMap<>(Comparator.reverseOrder());
		for(int i=0; i<m; i++){
			int b = sc.nextInt();
			long c = sc.nextLong();
			Integer tmp = map.get(c);
			if(map.get(c) == null){
				map.put(c, b);
			} else {
				map.put(c, b+tmp);
			}
		}
		for (Map.Entry<Long, Integer> kv : map.entrySet()) {
			Long key = kv.getKey();
			Integer count = kv.getValue();
			for(int i=0; i<count; i++){
				Long target = pq.poll();
				if(target<key){
					pq.add(key);
				} else {
					pq.add(target);
					break;
				}
			}
		}
		long ans = 0;
		while(pq.size() > 0){
			ans += pq.poll();
		}
		System.out.println(ans);
	}
}
