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.Arrays;
import java.util.Comparator;
import java.util.Scanner;

class Pair<F, S>{
	F first;
	S second;
	public Pair(F f, S s) {
		first = f;
		second = s;
	}
}

class Main{
	public static void main(String args[]){
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();
		Pair<Integer, Integer>[] nums = new Pair[N + M];
		for(int i = 0; i < N; i++) {
			nums[i] = new Pair<Integer, Integer>(sc.nextInt(), 1);
		}
		for(int i = 0; i < M; i++) {
			int B = sc.nextInt();
			int C = sc.nextInt();
			nums[N + i] = new Pair<Integer, Integer>(C, B);
		}
		Arrays.sort(nums, new Comparator<Pair<Integer, Integer>>(){
			public int compare(Pair<Integer, Integer> o1, Pair<Integer, Integer> o2) {
				return o2.first - o1.first;
			}
		});
		long ans = 0;
		int cardnum = 0;
		for(int i = 0; i < nums.length; i++) {
			int add_card_num = Math.min(nums[i].second, N - cardnum);
			cardnum += add_card_num;
			ans += (long)add_card_num * (long)nums[i].first;
			if(cardnum == N) break;
		}
		System.out.println(ans);
	}
}