Problem: You are given N integers A_1, A_2, ..., A_N.

Consider the sums of all non-empty subsequences of A. There are 2^N - 1 such sums, an odd number.

Let the list of these sums in non-decreasing order be S_1, S_2, ..., S_{2^N - 1}.

Find the median of this list, S_{2^{N-1}}.

Constraints

* 1 \leq N \leq 2000
* 1 \leq A_i \leq 2000
* All input values are integers.

Input

Input is given from Standard Input in the following format:


N
A_1 A_2 ... A_N


Output

Print the median of the sorted list of the sums of all non-empty subsequences of A.

Examples

Input

3
1 2 1


Output

2


Input

1
58


Output

58

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Arrays;
import java.io.IOException;
import java.io.Serializable;
import java.io.UncheckedIOException;
import java.io.Closeable;
import java.io.Writer;
import java.io.OutputStreamWriter;
import java.io.InputStream;

/**
 * Built using CHelper plug-in
 * Actual solution is at the top
 */
public class Main {
    public static void main(String[] args) throws Exception {
        Thread thread = new Thread(null, new TaskAdapter(), "", 1 << 27);
        thread.start();
        thread.join();
    }

    static class TaskAdapter implements Runnable {
        @Override
        public void run() {
            InputStream inputStream = System.in;
            OutputStream outputStream = System.out;
            FastInput in = new FastInput(inputStream);
            FastOutput out = new FastOutput(outputStream);
            CMedianSum solver = new CMedianSum();
            solver.solve(1, in, out);
            out.close();
        }
    }

    static class CMedianSum {
        public void solve(int testNumber, FastInput in, FastOutput out) {
            int n = in.readInt();
            int[] a = new int[n];
            in.populate(a);
            int sum = 0;
            for (int i = 0; i < n; i++) {
                sum += a[i];
            }
            BitSet bs = new BitSet(sum + 1);
            BitSet tmp = new BitSet(sum + 1);
            bs.set(0);

            for (int x : a) {
                tmp.copy(bs);
                tmp.rightShift(x);
                bs.or(tmp);
            }

            int ans = DigitUtils.ceilDiv(sum, 2);
            while (!bs.get(ans)) {
                ans++;
            }
            out.println(ans);
        }

    }

    static class FastInput {
        private final InputStream is;
        private byte[] buf = new byte[1 << 13];
        private int bufLen;
        private int bufOffset;
        private int next;

        public FastInput(InputStream is) {
            this.is = is;
        }

        public void populate(int[] data) {
            for (int i = 0; i < data.length; i++) {
                data[i] = readInt();
            }
        }

        private int read() {
            while (bufLen == bufOffset) {
                bufOffset = 0;
                try {
                    bufLen = is.read(buf);
                } catch (IOException e) {
                    bufLen = -1;
                }
                if (bufLen == -1) {
                    return -1;
                }
            }
            return buf[bufOffset++];
        }

        public void skipBlank() {
            while (next >= 0 && next <= 32) {
                next = read();
            }
        }

        public int readInt() {
            int sign = 1;

            skipBlank();
            if (next == '+' || next == '-') {
                sign = next == '+' ? 1 : -1;
                next = read();
            }

            int val = 0;
            if (sign == 1) {
                while (next >= '0' && next <= '9') {
                    val = val * 10 + next - '0';
                    next = read();
                }
            } else {
                while (next >= '0' && next <= '9') {
                    val = val * 10 - next + '0';
                    next = read();
                }
            }

            return val;
        }

    }

    static class DigitUtils {
        private DigitUtils() {
        }

        public static int floorDiv(int a, int b) {
            return a < 0 ? -ceilDiv(-a, b) : a / b;
        }

        public static int ceilDiv(int a, int b) {
            if (a < 0) {
                return -floorDiv(-a, b);
            }
            int c = a / b;
            if (c * b < a) {
                return c + 1;
            }
            return c;
        }

    }

    static class BitSet implements Serializable, Cloneable {
        private long[] data;
        private long tailAvailable;
        private int totalBit;
        private int m;
        private static final int SHIFT = 6;
        private static final int LOW = 63;
        private static final int BITS_FOR_EACH = 64;
        private static final long ALL_ONE = ~0L;
        private static final long ALL_ZERO = 0L;
        private static final int MAX_OFFSET = 63;

        public BitSet(int n) {
            totalBit = n;
            this.m = (totalBit + 64 - 1) / 64;
            data = new long[m];
            tailAvailable = oneBetween(0, offset(totalBit - 1));
        }

        public BitSet(BitSet bs) {
            this.data = bs.data.clone();
            this.tailAvailable = bs.tailAvailable;
            this.totalBit = bs.totalBit;
            this.m = bs.m;
        }

        public BitSet(BitSet bs, int l, int r) {
            totalBit = r - l + 1;
            tailAvailable = oneBetween(0, offset(totalBit - 1));
            data = Arrays.copyOfRange(bs.data, word(l), word(r) + 1);
            this.m = data.length;
            leftShift(offset(l));
            this.m = (totalBit + 64 - 1) / 64;
            data[m - 1] &= tailAvailable;
            for (int i = m; i < data.length; i++) {
                data[i] = 0;
            }
        }

        public boolean get(int i) {
            return (data[word(i)] & (1L << offset(i))) != 0;
        }

        public void set(int i) {
            data[word(i)] |= (1L << offset(i));
        }

        private static int word(int i) {
            return i >>> SHIFT;
        }

        private static int offset(int i) {
            return i & LOW;
        }

        private long oneBetween(int l, int r) {
            if (r < l) {
                return 0;
            }
            long lBegin = 1L << offset(l);
            long rEnd = 1L << offset(r);
            return (ALL_ONE ^ (lBegin - 1)) & ((rEnd << 1) - 1);
        }

        public int capacity() {
            return totalBit;
        }

        public void copy(BitSet bs) {
            int n = Math.min(this.m, bs.m);
            System.arraycopy(bs.data, 0, data, 0, n);
            Arrays.fill(data, n, n, 0);
        }

        public void or(BitSet bs) {
            int n = Math.min(this.m, bs.m);
            for (int i = 0; i < n; i++) {
                data[i] |= bs.data[i];
            }
        }

        public int nextSetBit(int start) {
            int offset = offset(start);
            int w = word(start);
            if (offset != 0) {
                long mask = oneBetween(offset, 63);
                if ((data[w] & mask) != 0) {
                    return Long.numberOfTrailingZeros(data[w] & mask) + w * BITS_FOR_EACH;
                }
                w++;
            }

            while (w < m && data[w] == ALL_ZERO) {
                w++;
            }
            if (w >= m) {
                return capacity();
            }
            return Long.numberOfTrailingZeros(data[w]) + w * BITS_FOR_EACH;
        }

        public void leftShift(int n) {
            int wordMove = word(n);
            int offsetMove = offset(n);
            int rshift = 63 - (offsetMove - 1);

            if (offsetMove != 0) {
                //slightly
                for (int i = 0; i < m; i++) {
                    if (i > 0) {
                        data[i - 1] |= data[i] << rshift;
                    }
                    data[i] >>>= offsetMove;
                }
            }
            if (wordMove > 0) {
                for (int i = 0; i < m; i++) {
                    if (i >= wordMove) {
                        data[i - wordMove] = data[i];
                    }
                    data[i] = 0;
                }
            }
        }

        public void rightShift(int n) {
            int wordMove = word(n);
            int offsetMove = offset(n);
            int lShift = MAX_OFFSET + 1 - offsetMove;

            if (offsetMove != 0) {
                //slightly
                for (int i = m - 1; i >= 0; i--) {
                    if (i + 1 < m) {
                        data[i + 1] |= data[i] >>> lShift;
                    }
                    data[i] <<= offsetMove;
                }
            }
            if (wordMove > 0) {
                for (int i = m - 1; i >= 0; i--) {
                    if (i + wordMove < m) {
                        data[i + wordMove] = data[i];
                    }
                    data[i] = 0;
                }
            }

            data[m - 1] &= tailAvailable;
        }

        public BitSet clone() {
            return new BitSet(this);
        }

        public String toString() {
            StringBuilder builder = new StringBuilder("{");
            for (int i = nextSetBit(0); i < capacity(); i++) {
                builder.append(i).append(',');
            }
            if (builder.length() > 1) {
                builder.setLength(builder.length() - 1);
            }
            builder.append("}");
            return builder.toString();
        }

    }

    static class FastOutput implements AutoCloseable, Closeable, Appendable {
        private StringBuilder cache = new StringBuilder(10 << 20);
        private final Writer os;

        public FastOutput append(CharSequence csq) {
            cache.append(csq);
            return this;
        }

        public FastOutput append(CharSequence csq, int start, int end) {
            cache.append(csq, start, end);
            return this;
        }

        public FastOutput(Writer os) {
            this.os = os;
        }

        public FastOutput(OutputStream os) {
            this(new OutputStreamWriter(os));
        }

        public FastOutput append(char c) {
            cache.append(c);
            return this;
        }

        public FastOutput append(int c) {
            cache.append(c);
            return this;
        }

        public FastOutput println(int c) {
            return append(c).println();
        }

        public FastOutput println() {
            cache.append(System.lineSeparator());
            return this;
        }

        public FastOutput flush() {
            try {
                os.append(cache);
                os.flush();
                cache.setLength(0);
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }
            return this;
        }

        public void close() {
            flush();
            try {
                os.close();
            } catch (IOException e) {
                throw new UncheckedIOException(e);
            }
        }

        public String toString() {
            return cache.toString();
        }

    }
}