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) throws Exception {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        long[] li = new long[n];
        for(int i = 0; i < n; i++){
            li[i] = sc.nextLong();
        }
        Arrays.sort(li);
        Change[] changes = new Change[m];
        for(int i = 0; i < m; i++){
            int count = sc.nextInt();
            long diff = sc.nextLong();
            changes[i] = new Change(count,diff);
        }
        Arrays.sort(changes);
        long ans = 0;
		int j = 0;
		for (int i = 0; i < n; i++) {
			if (j >= m || li[i] >= changes[j].diff) {
				ans += li[i];
			} else {
				ans += changes[j].diff;
				changes[j].count--;
				if (changes[j].count == 0) {
					j++;
				}
			}
		}
		System.out.println(ans);
    }
}

class Change implements Comparable<Change>{
    int count;
    long diff;
    public Change(int c, long d){
        this.count = c;
        this.diff = d;
    }
    public int compareTo(Change c){
        if(this.diff < c.diff){
            return 1;
        }else if(this.diff > c.diff){
            return -1;
        }
        return 0;
    }
}

