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.Scanner;
class Main{

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);			//文字の入力


		int n = sc.nextInt();
		int m = sc.nextInt();
		int[] A = new int[n];
		Pair[] pairs = new Pair[m];
	
		for(int i = 0;i < n;i++){
			A[i] = sc.nextInt();
		}
		Arrays.sort(A);
		
		for(int i = 0;i < m;i++){
			Pair pair = new Pair();
			pair.from = sc.nextInt();
			pair.end = sc.nextInt();
			pairs[i] = pair;
		}
		Arrays.sort(pairs);
//		
//		for(int i = 0;i < m;i++){
//			System.out.println(pairs[i].end);
//		}
//		System.out.println();
		
		int index = 0;
		for(int i = 0;i < m;i++){
			int candidate = pairs[i].end;
			for(int j = 0;j < pairs[i].from;j++){
				if(A[index] < candidate){
					A[index] = candidate;
					index++;
					if(index >= n){
						allsum(A);
						return;
					}
	 			}else{
	 				break;
	 			}
			}	
		}
		
		allsum(A);
		
		
		

		
		
	}
	
	static void allsum(int[] A){
		long ans = 0;
		for(int i = 0;i < A.length;i++){
//			System.out.println(A[i]);
			ans += A[i];
		}
		System.out.print(ans);
	}


	static int gcd(int a,int b){				//最大公約数を返す
		if(b == 0){
			return a;
		}else{
			return gcd(b, a%b);
		}
	}





}



class Pair implements Comparable{
	int from;
	int end;
	@Override
	public int compareTo(Object other) {
		Pair otherpair = (Pair)other;

		return  otherpair.end - end;
	}
}


