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.Map;
import java.util.Scanner;
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();

		TreeMap<Integer, Integer> map = new TreeMap<>();
		for (int i=0;i<n;i++) {
			int a = sc.nextInt();
			int x = map.containsKey(a) ? map.get(a) : 0;

			map.put(a, x+1);
		}

		for (int i=0;i<m;i++) {
			int b = sc.nextInt();
			int c = sc.nextInt();

			int pos = map.firstKey();
			while (b>0 && pos<c) {
				int d = map.get(pos);
				if (b>=d) {
					
					map.remove(pos);
					int x = map.containsKey(c) ? map.get(c) : 0;
					map.put(c, x+d);
					pos=map.higherKey(pos);
					b-=d;
				} else {
					
					map.put(pos, d-b);
					int x = map.containsKey(c) ? map.get(c) : 0;
					map.put(c, x+b);
					
					b=0;
				}
			}
		}
		
		long ans = 0;
		
		for (Map.Entry<Integer, Integer> e : map.entrySet()) {
			ans += (long)e.getKey() * (long)e.getValue();
		}

		System.out.println(ans);
	}
}




