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.*;

public class Main {
    public static void main(String[] args) throws Exception {
        
        Scanner sc = new Scanner(System.in);
        int N = sc.nextInt();
        int M = sc.nextInt();
        
        Queue<Integer> queue = new PriorityQueue<>();        
        for(int i = 0; i < N; i++){
            int A = sc.nextInt();
            queue.add(A);
        }
        
        int[][] BC = new int[M][2];
        for(int i = 0; i < M; i++){
            int B = sc.nextInt();
            int C = sc.nextInt();
            
            BC[i][0] = B;
            BC[i][1] = C;
        }
        
        Arrays.sort( BC, (BC1, BC2) -> BC2[1] - BC1[1] );
        
        for(int i = 0; i < M; i++){
            while( queue.peek() < BC[i][1] && BC[i][0] > 0 ){
                queue.add(BC[i][1]);
                queue.poll();
                BC[i][0]--;
            }
        }
        
        long total = 0;
        for(int i : queue){
            total += i;
        }
        
        System.out.println(total);

    }
}
