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.io.InputStream;
import java.io.PrintStream;
import java.util.Arrays;
import java.util.Scanner;

public class Main {
	InputStream in = System.in;
	PrintStream out = System.out;

	public void _main(String[] args) {
		Scanner sc = new Scanner(in);

		int N = sc.nextInt();
		int M = sc.nextInt();

		int[] A = new int[N];
		int[][] BC = new int[M][2];

		for (int i = 0; i < N; i++) {
			A[i] = sc.nextInt();
		}
		for (int i = 0; i < M; i++) {
			BC[i][0] = sc.nextInt();
			BC[i][1] = sc.nextInt();
		}

		Arrays.sort(A);
		Arrays.sort(BC, (a, b) -> Integer.compare(b[1], a[1])); //降順

		int bci = 0;
		for (int ai = 0; ai < A.length; ai++) {
			if (A[ai] >= BC[bci][1]) {
				break;
			}
			A[ai] = BC[bci][1];
			BC[bci][0]--;
			if (BC[bci][0] <= 0) {
				bci++;
			}
			if (bci >= BC.length) {
				break;
			}
		}

		long ans = 0;
		for (int i = 0; i < N; i++) {
			ans += A[i];
		}

		out.println(ans);

		sc.close();

	}

	public static void main(String[] args) {
		new Main()._main(args);
	}

}
