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) {
		Scanner sc = new Scanner(System.in);
		int N = sc.nextInt();
		int M = sc.nextInt();
		long[] A = new long[N];
		
		for(int i = 0; i < N; i++) {
			A[i] = sc.nextLong();
		}
		
		long[][] x = new long[M][2];
		
		for(int i = 0; i < M; i++) {
			x[i][0] = sc.nextLong();
			x[i][1] = sc.nextLong();
		}
		
		Arrays.sort(x, (a1, a2) -> Long.compare(a1[1], a2[1]));
		Arrays.sort(A);
		
		long[] ans = new long[N];
		int num = 0;
		
		for(int i = M - 1; i >= 0; i--) {
			while(x[i][0] >= 1 && num <= N - 1) {
				ans[num] = x[i][1];
				x[i][0]--;
				num++;
			}
			if(num > N - 1) {
				break;
			}
		}
		
		for(int i = N - 1; i >= 0; i--) {
			if(A[i] > ans[i]) {
				ans[i] = A[i];
			} else {
				break;
			}
		}
		
		long sum = 0;
		
		for(int i = 0; i < N; i++) {
			sum += ans[i];
		}
		
		System.out.println(sum);
	}
}
