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.lang.Math;
import java.util.Scanner;
import java.util.Arrays;

class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);

        int N = sc.nextInt();
        int M = sc.nextInt();
        int[] A = new int[N];
        int[][] rewrites = new int[M][2];  // [num, target]

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

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

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

        // System.out.println(Arrays.deepToString(rewrites));

        long answer = 0;
        int pos = 0;
        for (int i = 0; i < M; i++) {
            boolean breakOuter = false;
            for (int j = 0; j < rewrites[i][0]; j++) {
                if (pos >= A.length) {
                    breakOuter = true;
                    break;
                }

                if (rewrites[i][1] > A[pos]) {
                    answer += rewrites[i][1];
                    pos++;
                }
                else {
                    breakOuter = true;
                    break;
                }
            }
            if (breakOuter) { break; }
        }

        for (int i = pos; i < A.length; i++) {
            answer += A[i];
        }

        System.out.println(answer);
    }
}
