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 final int MOD = 1000000007;
  public static final int INF = 1000000000;
  public static void main(String[] args) {
    Scanner sc = new Scanner(System.in);
    int N = sc.nextInt();
    int M = sc.nextInt();
    Integer A[] = new Integer[N];
    Integer D[][] = new Integer[M][2];
    for(int i=0; i<N; i++) A[i] = sc.nextInt();
    for(int i=0; i<M; i++){
      D[i][0] = sc.nextInt();
      D[i][1] = sc.nextInt();
    }
    Arrays.sort(A);
    Arrays.sort(D, (a,b) -> Integer.compare(a[1], b[1]));
    int j = 0;
    int k;
    boolean check = true;
    for(int i=M-1; i>=0; i--){
      if(check == false) break;
      k = 0;
      while(k < D[i][0]){
        if(j >= N){
          check = false;
          break;
        }
        if(A[j] < D[i][1]){
          A[j] = D[i][1];
          j++;
          k++;
        }else{
          check = false;
          break;
        }
      }
    }
    long ans = 0L;
    for(int i=0; i<N; i++){
      ans += A[i];
    }
    System.out.println(ans);
  }

  public static int gcd(int a, int b){
    if(b == 0) return a;
    return gcd(b, a%b);
  }
}