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 {
        // Your code here!
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int m = sc.nextInt();
        
        int[] cards = new int[n];
        for (int i = 0; i < n; i++) {
            cards[i] = sc.nextInt();
        }
        Arrays.sort(cards);
        
        int[][] ab = new int[m][2];
        for (int i = 0; i < m; i++) {
            int k = sc.nextInt();
            int v = sc.nextInt();
            ab[i][0] = v;
            ab[i][1] = k;
        }        
        Arrays.sort(ab, (x, y) -> Integer.compare(x[0], y[0]));
        
        int idx = 0;
        for (int i = m - 1; i >= 0; i--) {
            boolean end = false;
            int k = ab[i][1];
            int v = ab[i][0];
            
            while (k-- > 0) {
                if (cards[idx] >= v) {
                    end = true;
                    break;
                }
                cards[idx] = v;
                idx++;
                if (idx == n) {
                    end = true;
                    break;
                }
            }
            if (end) break;
        }
        
        long answer = 0;
        for (int val : cards) {
            answer += val;
        }
        
        System.out.println(answer);
    }
}