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 scanner = new Scanner(System.in);
        int N = scanner.nextInt();
        int M = scanner.nextInt();
        long[] A = new long[N];
        for (int i = 0; i < N; i++) {
            A[i] = scanner.nextLong();
        }
        Arrays.sort(A);

        BC[] bc = new BC[M];
        for (int i = 0; i < M; i++) {
            bc[i] = new BC(scanner.nextInt(), scanner.nextLong());
        }
        long[] D = new long[N];
        Arrays.sort(bc);
        reverse(bc);
        int idx = 0;
        outer: for (int i = 0; i < M; i++) {
            for (int j = 0; j < bc[i].B; j++) {
                if (idx == N) {
                    break outer;
                }
                D[idx++] = bc[i].C;
            }
        }
        Arrays.sort(D);
        reverse(D);

        for (int x = 0; x < N; x++) {
            if (A[x] < D[x]) {
                A[x] = D[x];
            }
        }
        long ans = 0;
        for (long a : A) {
            ans += a;
        }

        System.out.println(ans);

    }

    public static void reverse(BC[] arr) {
        for (int i = 0; i < arr.length / 2; i++) {
            BC tmp = arr[i];
            arr[i] = arr[arr.length - i - 1];
            arr[arr.length - i - 1] = tmp;
        }
    }

    public static void reverse(long[] arr) {
        for (int i = 0; i < arr.length / 2; i++) {
            long tmp = arr[i];
            arr[i] = arr[arr.length - i - 1];
            arr[arr.length - i - 1] = tmp;
        }
    }

    static class BC implements Comparable<BC> {
        int B;
        long C;

        public BC(int b, long c) {
            this.B = b;
            this.C = c;
        }

        @Override
        public int compareTo(BC o) {

            return Long.compare(this.C, o.C);
        }

    }
}
