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.Comparator;
import java.util.Scanner;
import java.util.TreeMap;

class Main {
	public static void main(String args[]) {
		StringBuilder sb = new StringBuilder();
		Scanner sc = new Scanner(System.in);
		int n = sc.nextInt();
		int m = sc.nextInt();
		TreeMap<Integer, Integer> tm = new TreeMap<>(Comparator.reverseOrder());
		int a;
		for (int i = 0; i < n; i++) {
			a = sc.nextInt();
			if (tm.containsKey(a)) {
				tm.put(a, tm.get(a) + 1);
			} else {
				tm.put(a, 1);
			}
		}

		int b, c;
		for (int i = 0; i < m; i++) {
			b = sc.nextInt();
			c = sc.nextInt();
			if (tm.containsKey(c)) {
				tm.put(c, tm.get(c) + b);
			} else {
				tm.put(c, b);
			}
		}
		long ans = 0;
		for (int i : tm.keySet()) {
			if (n - tm.get(i) > 0) {
				ans += (long) i * tm.get(i);
				n -= tm.get(i);
			} else {
				ans += (long) i * n;
				break;
			}
		}
		System.out.println(ans);
	}
}