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 seer = new Scanner(System.in);
		int n = seer.nextInt(); int m = seer.nextInt();
		PriorityQueue<Long> set = new PriorityQueue<>();
		for(int i = 0; i < n; i++){
			set.add(seer.nextLong());
		}
		Pair[] ps = new Pair[m];
		for(int i = 0; i < m; i++){
			int b = seer.nextInt();
			int c = seer.nextInt();
			ps[i] = new Pair(b, c);
		}
		Arrays.sort(ps);
		for(int i = m-1; i >= 0; i--){
			int b = ps[i].b; long c = ps[i].c;
			while(b > 0){
				long x = set.poll();
				if(x < c){
					set.add(c);
					b--;
				}
				else{
					set.add(x);
					break;
				}
			}
			if(b > 0) break;
		}
		long tot = 0;
		for(long a: set) tot += a;
		System.out.println(tot);
	}
	static class Pair implements Comparable<Pair>{
		int b; long c;
		public Pair(int b, long c){
			this.b = b; this.c = c;
		}
		@Override
		public int compareTo(Pair P) {
			if(c < P.c) return -1;
			else if(c == P.c) return 0;
			else return 1;
		}
	}
}
