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.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.*;


public class Main {
    int N,M;
    int[] A, B, C;
    Pair[] pairs;

    private class Pair implements Comparable<Pair> {
        int b,c;
        public Pair(int b, int c) {
            this.b = b;
            this.c = c;
        }

        public int compareTo(Pair other) {
            return other.c - this.c;
        }
    }

    private void solve() {
        N = nextInt();
        M = nextInt();
        A = new int[N];
        for(int i = 0;i < N;i++) {
            A[i] = nextInt();
        }

        B = new int[M];
        C = new int[M];
        pairs = new Pair[M];
        for(int i = 0;i < M;i++) {
            B[i] = nextInt();
            C[i] = nextInt();
            pairs[i] = new Pair(B[i], C[i]);
        }

        Arrays.sort(A);
        Arrays.sort(pairs);

        int idx = 0;
        for(int i = 0;i < M;i++) {
            while(idx < N && pairs[i].b > 0 && A[idx] < pairs[i].c) {
                pairs[i].b--;
                A[idx] = pairs[i].c;
                idx++;
            }
        }

        long ans = 0;
        for(int i = 0;i < N;i++) {
            ans += A[i];
        }

        out.println(ans);
    }

    public static void main(String[] args) {
        out.flush();
        new Main().solve();
        out.close();
    }

    /* Input */
    private static final InputStream in = System.in;
    private static final PrintWriter out = new PrintWriter(System.out);
    private final byte[] buffer = new byte[4096];
    private int p = 0;
    private int buflen = 0;

    private boolean hasNextByte() {
        if (p < buflen)
            return true;
        p = 0;
        try {
            buflen = in.read(buffer);
        } catch (IOException e) {
            e.printStackTrace();
        }
        if (buflen <= 0)
            return false;
        return true;
    }

    public boolean hasNext() {
        while (hasNextByte() && !isPrint(buffer[p])) {
            p++;
        }
        return hasNextByte();
    }

    private boolean isPrint(int ch) {
        if (ch >= '!' && ch <= '~')
            return true;
        return false;
    }

    private int nextByte() {
        if (!hasNextByte())
            return -1;
        return buffer[p++];
    }

    public String next() {
        if (!hasNext())
            throw new NoSuchElementException();
        StringBuilder sb = new StringBuilder();
        int b = -1;
        while (isPrint((b = nextByte()))) {
            sb.appendCodePoint(b);
        }
        return sb.toString();
    }

    public int nextInt() {
        return Integer.parseInt(next());
    }

    public long nextLong() {
        return Long.parseLong(next());
    }

    public double nextDouble() {
        return Double.parseDouble(next());
    }
}
