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[] args) {
		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();
		}
		int cnt=0;
		List<int[]> b_c = new ArrayList<int[]>();
		for (int i=0;i<M;i++) {
			int b=sc.nextInt();
			if (cnt<100005) {
				cnt+=b;
			}
			int c=sc.nextInt();
			int[] b__c={b,c};
			b_c.add(b__c);
		}
		Arrays.sort(A);

        Comparator<int[]> comparator = new Comparator<int[]>() {
            @Override
            public int compare(int[] o1, int[] o2) {
                return Integer.valueOf(o2[1]).compareTo(Integer.valueOf(o1[1]));
            }
        };
        Collections.sort(b_c,comparator);

        List<Integer> C = new ArrayList<Integer>();
        int len=0;
        loop:for (int i=0;i<M;i++) {
        	int b=b_c.get(i)[0];
        	int c=b_c.get(i)[1];
        	for (int j=0;j<b;j++) {
        		C.add(c);
        		len++;
        		if (len>100005) {
        			break loop;
        		}
        	}
        }
 //       System.out.println(Arrays.toString(A));
   //     System.out.println(C);

        for (int i=0;i<Math.min(cnt,N);i++) {
        	if (A[i]<=C.get(i)) {
        		A[i]=C.get(i);
        	} else {
        		break;
        	}
        }
        long ans=0L;
        for (int i=0;i<N;i++) {
        	ans+=(long)A[i];
        }
        System.out.println(ans);

	}
}