import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintWriter;
import java.util.Arrays;
import java.util.PriorityQueue;
import java.io.BufferedWriter;
import java.util.InputMismatchException;
import java.io.IOException;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 *
 * @author maheshwari29
 */
public class Main {
    public static void main(String[] args) {
        InputStream inputStream = System.in;
        OutputStream outputStream = System.out;
        InputReader in = new InputReader(inputStream);
        OutputWriter out = new OutputWriter(outputStream);
        DIntegerCards solver = new DIntegerCards();
        solver.solve(1, in, out);
        out.close();
    }

    static class DIntegerCards {
        public void solve(int testNumber, InputReader in, OutputWriter out) {
            int i, j;
            int n = in.ni();
            int m = in.ni();
            long a[] = in.nla(n);
            DIntegerCards.pair p[] = new DIntegerCards.pair[m];
            for (i = 0; i < m; i++) {
                int b = in.ni();
                long c = in.nl();
                p[i] = new DIntegerCards.pair(c, b);
            }
            PriorityQueue<Long> pq = new PriorityQueue<>();
            for (long c : a)
                pq.add(c);
            Arrays.sort(p);
            int counter = 0;
            long ans = 0;
            while (counter < m) {
                long z = p[counter].y;
                long y = p[counter].x;
                while (pq.size() != 0 && pq.peek() < y && z > 0) {
                    pq.poll();
                    ans += y;
                    z--;
                }
                counter++;
            }
            while (pq.size() != 0)
                ans += pq.poll();
            out.println(ans);
        }

        static class pair implements Comparable<DIntegerCards.pair> {
            long x;
            long y;

            public pair(long x, long y) {
                this.x = x;
                this.y = y;
            }

            public int compareTo(DIntegerCards.pair arg0) {
                if (x < arg0.x) return 1;
                else if (x == arg0.x) {
                    if (y < arg0.y) return -1;
                    else if (y > arg0.y) return 1;
                    else return 0;
                } else return -1;
            }

        }

    }

    static class OutputWriter {
        private final PrintWriter writer;

        public OutputWriter(OutputStream outputStream) {
            writer = new PrintWriter(new BufferedWriter(new OutputStreamWriter(outputStream)));
        }

        public OutputWriter(Writer writer) {
            this.writer = new PrintWriter(writer);
        }

        public void close() {
            writer.close();
        }

        public void println(long i) {
            writer.println(i);
        }

    }

    static class InputReader {
        private InputStream stream;
        private byte[] buf = new byte[1024];
        private int curChar;
        private int numChars;
        private InputReader.SpaceCharFilter filter;

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

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

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

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

        public boolean isSpaceChar(int c) {
            if (filter != null) {
                return filter.isSpaceChar(c);
            }
            return isWhitespace(c);
        }

        public static boolean isWhitespace(int c) {
            return c == ' ' || c == '\n' || c == '\r' || c == '\t' || c == -1;
        }

        public long[] nla(int n) {
            long[] array = new long[n];
            for (int i = 0; i < n; ++i) array[i] = nl();
            return array;
        }

        public interface SpaceCharFilter {
            public boolean isSpaceChar(int ch);

        }

    }
}



Measured memory_bytes: 34580