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.*;

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

        int m = M-1;
        int n = N-1;
        int count = 0;
        long total = 0;
        while(count < N){
            int b = BC[m][0];
            int c = BC[m][1];
            while(b>0 && n>=0 && count < N){
                count++;
                if(c<=A[n]){
                    total += A[n];
                    n--;
                }
                else{
                    total += c;
                    b--;
                }
            }
            m--;
            if(m<0){
                while(count < N){
                    count++;
                    total += A[n];
                    n--;
                }
                break;
            }
        }
        System.out.println(total);
    }
}