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<Integer> queue = new PriorityQueue<>();
		for (int i = 0; i < n; i++) {
		    queue.add(sc.nextInt());
		}
		Change[] changes = new Change[m];
		for (int i = 0; i < m; i++) {
		    changes[i] = new Change(sc.nextInt(), sc.nextInt());
		}
		Arrays.sort(changes);
		long total = 0;
		for (Change x : changes) {
		    if (queue.size() == 0 || queue.peek() > x.value) {
		        break;
		    }
		    for (int i = 0; i < x.times; i++) {
		        if (queue.size() == 0 || queue.peek() > x.value) {
		            break;
		        }
		        total += x.value;
		        queue.poll();
		    }
		}
		while (queue.size() > 0) {
		    total += queue.poll();
		}
		System.out.println(total);
	}

    static class Change implements Comparable<Change> {
        int value;
        int times;
        
        public Change (int times, int value) {
            this.value = value;
            this.times = times;
        }
        
        public String toString() {
            return "value:" + value + " times:" + times;
        }
        public int compareTo(Change another) {
            return another.value - value;
        }
    }

}
