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.Scanner;
import java.util.Arrays;

class QuickSort {
    static void sort(int[] a, int[] b){
        partialySort(a, b, 0, a.length - 1);
    }

    static void partialySort(int[] a, int[] b, int left, int right){
        if(right <= left)
            return;
        
        int pivot = a[(left+right)/2];
        int i = left;
        int j = right;
        int temp;
        while(i <= j){
            while(a[i] < pivot)
                i++;
            while(a[j] > pivot)
                j--;
            if(i <= j){
                temp = a[i];
                a[i] = a[j];
				a[j] = temp;
				temp = b[i];
				b[i] = b[j];
				b[j] = temp;
                i++;
                j--;
            }
        }

        partialySort(a, b, left, j);
        partialySort(a, b, i, right);
    }
}

public class Main {
    static Scanner stdIn = new Scanner(System.in);
    public static void main(String[] args){
		int n = stdIn.nextInt();
		int m = stdIn.nextInt();
		Integer[] a = new Integer[n];
		for(int i=0; i<n; i++){
			a[i] = stdIn.nextInt();
		}
		int[] b = new int[m];
		int[] c = new int[m];
		for(int i=0; i<m; i++){
			b[i] = stdIn.nextInt();
			c[i] = stdIn.nextInt();
		}

		Arrays.sort(a);

		QuickSort.sort(c, b);

		int aIdx = 0;
		int bcIdx = m-1;
		while(aIdx < n && bcIdx >= 0 && a[aIdx] < c[bcIdx]){
			a[aIdx] = c[bcIdx];
			aIdx++;
			b[bcIdx]--;
			if(b[bcIdx] <= 0){
				bcIdx--;
			}
		}

		long sum = 0;
		for(int i=0; i<n; i++){
			sum += a[i];
		}
		System.out.println(sum);
	}
}
