import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.AbstractCollection;
import java.util.PriorityQueue;
import java.util.InputMismatchException;
import java.io.IOException;
import java.util.Comparator;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        FastReader in = new FastReader(inputStream);
        PrintWriter out = new PrintWriter(outputStream);
        DIntegerCards solver = new DIntegerCards();
        solver.solve(1, in, out);
        out.close();
    }

    static class DIntegerCards {
        public void solve(int testNumber, FastReader in, PrintWriter out) {
            int n = in.nextInt();
            int m = in.nextInt();
            int[] a = in.nextIntArray(n);
            PriorityQueue<Integer> priorityQueue = new PriorityQueue<>();
            for (int aa : a) priorityQueue.add(aa);
            int[][] ord = new int[m][];
            for (int i = 0; i < m; ++i) {
                ord[i] = new int[]{in.nextInt(), in.nextInt()};
            }
            Arrays.sort(ord, new Comparator<int[]>() {

                public int compare(int[] o1, int[] o2) {
                    return o2[1] - o1[1];
                }
            });
            for (int[] o : ord) {
                int count = o[0];
                int num = o[1];
                while (!priorityQueue.isEmpty() && priorityQueue.peek() < num) {
                    priorityQueue.poll();
                    priorityQueue.add(num);
                    --count;
                    if (count == 0) break;
                }
            }
            long ans = 0;
            while (!priorityQueue.isEmpty()) ans += priorityQueue.poll();
            out.println(ans);
        }

    }

    static class FastReader {
        private InputStream stream;
        private byte[] buf = new byte[8192];
        private int curChar;
        private int pnumChars;

        public FastReader(InputStream stream) {
            this.stream = stream;
        }

        private int pread() {
            if (pnumChars == -1) {
                throw new InputMismatchException();
            }
            if (curChar >= pnumChars) {
                curChar = 0;
                try {
                    pnumChars = stream.read(buf);
                } catch (IOException e) {
                    throw new InputMismatchException();
                }
                if (pnumChars <= 0) {
                    return -1;
                }
            }
            return buf[curChar++];
        }

        public int nextInt() {
            int c = pread();
            while (isSpaceChar(c))
                c = pread();
            int sgn = 1;
            if (c == '-') {
                sgn = -1;
                c = pread();
            }
            int res = 0;
            do {
                if (c == ',') {
                    c = pread();
                }
                if (c < '0' || c > '9') {
                    throw new InputMismatchException();
                }
                res *= 10;
                res += c - '0';
                c = pread();
            } while (!isSpaceChar(c));
            return res * sgn;
        }

        public int[] nextIntArray(int n) {
            int[] array = new int[n];
            for (int i = 0; i < n; i++) {
                array[i] = nextInt();
            }
            return array;
        }

        private boolean isSpaceChar(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

    }
}



Measured memory_bytes: 32288