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.io.*;
import java.util.*;


public class Main {
    static ArrayList<Integer>[] graph;
    static TreeMap<Long,Long> valTime = new TreeMap<>();
    public static void main(String[] args) throws Exception {
        //Scanner sc = new Scanner(System.in);
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String[] buf = reader.readLine().split(" ");
        int n = Integer.parseInt(buf[0]), m = Integer.parseInt(buf[1]);
        buf = reader.readLine().split(" ");
        for(String w:buf){
            long cur = Long.parseLong(w);
            putHelp(cur,1);
        }
        for(int i=0;i<m;i++){
            buf = reader.readLine().split(" ");
            long b = Long.parseLong(buf[0]), c = Long.parseLong(buf[1]);
            putHelp(c,b);
        }
        long cnt = 0,ans = 0;
        while(cnt<n){
            Map.Entry<Long,Long> cur = valTime.pollLastEntry();
            long val = cur.getKey(), time = cur.getValue();
            long toadd = Math.min(time,n-cnt);
            ans += toadd*val;
            cnt += toadd;
        }
        System.out.println(ans);


    }
    static void putHelp(long val, long time){
        if(!valTime.containsKey(val)) valTime.put(val,time);
        else valTime.put(val,valTime.get(val)+time);
    }
}

