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;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int N = in.nextInt();
		int M = in.nextInt();
		long[] A = new long[N];
		for (int i = 0; i < N; i++) {
			A[i] = in.nextLong();
		}
		Arrays.sort(A);
		long[][] BC = new long[M][2];
		for (int i = 0; i < M; i++) {
			BC[i][0] = in.nextLong();
			BC[i][1] = in.nextLong();
		}
		Arrays.sort(BC, (a, b) -> Long.compare(b[1], a[1]));

		long sum = 0;
		int index = 0;
		for (int i = 0; i < M; i++) {
			for (long j = 0; index < A.length && j < BC[i][0]; j++) {
				sum += Math.max(A[index], BC[i][1]);
				index++;
			}
		}

		for (int i = index; i < A.length; i++) {
			sum += A[i];
		}
		System.out.println(sum);
		in.close();
	}
}