Problem: Let's call two strings a and b (both of length k) a bit similar if they have the same character in some position, i. e. there exists at least one i ∈ [1, k] such that a_i = b_i.

You are given a binary string s of length n (a string of n characters 0 and/or 1) and an integer k. Let's denote the string s[i..j] as the substring of s starting from the i-th character and ending with the j-th character (that is, s[i..j] = s_i s_{i + 1} s_{i + 2} ... s_{j - 1} s_j).

Let's call a binary string t of length k beautiful if it is a bit similar to all substrings of s having length exactly k; that is, it is a bit similar to s[1..k], s[2..k+1], ..., s[n-k+1..n].

Your goal is to find the lexicographically smallest string t that is beautiful, or report that no such string exists. String x is lexicographically less than string y if either x is a prefix of y (and x ≠ y), or there exists such i (1 ≤ i ≤ min(|x|, |y|)), that x_i < y_i, and for any j (1 ≤ j < i) x_j = y_j.

Input

The first line contains one integer q (1 ≤ q ≤ 10000) — the number of test cases. Each test case consists of two lines.

The first line of each test case contains two integers n and k (1 ≤ k ≤ n ≤ 10^6). The second line contains the string s, consisting of n characters (each character is either 0 or 1).

It is guaranteed that the sum of n over all test cases does not exceed 10^6.

Output

For each test case, print the answer as follows:

  * if it is impossible to construct a beautiful string, print one line containing the string NO (note: exactly in upper case, you can't print No, for example); 
  * otherwise, print two lines. The first line should contain the string YES (exactly in upper case as well); the second line — the lexicographically smallest beautiful string, consisting of k characters 0 and/or 1. 

Example

Input


7
4 2
0110
4 2
1001
9 3
010001110
9 3
101110001
10 3
0101110001
10 10
1111111111
11 10
11111111110


Output


YES
11
YES
00
YES
010
YES
101
NO
YES
0000000001
YES
0000000010

Solution (in JAVA):

Solution:
import java.io.OutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.util.Arrays;
import java.io.OutputStreamWriter;
import java.io.OutputStream;
import java.io.IOException;
import java.io.Serializable;
import java.io.UncheckedIOException;
import java.io.Closeable;
import java.io.Writer;
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 << 28);
        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);
            EABitSimilar solver = new EABitSimilar();
            int testCount = Integer.parseInt(in.next());
            for (int i = 1; i <= testCount; i++)
                solver.solve(i, in, out);
            out.close();
        }
    }

    static class EABitSimilar {
        int limit = (int) 1e6;
        int mod = (int) 1e9 + 7;
        HashData hd1 = new HashData(limit, mod, 31);
        HashData hd2 = new HashData(limit, mod, 13);
        IntRangeHash rh = new IntRangeHash(hd1, hd2, limit);
        LongHashSet[] hs = new LongHashSet[]{new LongHashSet(limit, false), new LongHashSet(limit, false)};
        ModifiableHash mh = new ModifiableHash(hd1, hd2, limit);

        public void solve(int testNumber, FastInput in, FastOutput out) {
            int n = in.ri();
            int k = in.ri();
            char[] s = new char[n];
            for (int i = 0; i < n; i++) {
                s[i] = (char) (in.rc() - '0');
            }
            rh.populate(i -> 1 - s[i], n);
            for (int i = 0; i < 2; i++) {
                hs[i].clear();
            }
            mh.init(k - 1);
            for (int i = 0; i + k <= n; i++) {
                int l = i;
                int r = i + k - 1;
                hs[s[r]].add(rh.hash(l, r - 1));
            }

            if (!minHash(0, k - 1)) {
                out.println("NO");
                return;
            }
            out.println("YES");
            for (int i = 0; i < k - 1; i++) {
                out.append(mh.get(i));
            }
            if (hs[1].contain(mh.hash())) {
                out.append(1);
            } else {
                out.append(0);
            }
            out.println();
        }

        public boolean minHash(int i, int n) {
            if (i >= n) {
                long h = mh.hash();
                return !hs[0].contain(h) || !hs[1].contain(h);
            }
            mh.set(i, 0);
            if (minHash(i + 1, n)) {
                return true;
            }
            mh.set(i, 1);
            return minHash(i + 1, n);
        }

    }

    static interface RangeHash {
    }

    static class RandomWrapper {
        private MersenneTwisterFast random;
        public static final RandomWrapper INSTANCE = new RandomWrapper();

        public RandomWrapper() {
            this(new MersenneTwisterFast());
        }

        public RandomWrapper(MersenneTwisterFast random) {
            this.random = random;
        }

        public RandomWrapper(long seed) {
            this(new MersenneTwisterFast(seed));
        }

        public int nextInt(int l, int r) {
            return random.nextInt(r - l + 1) + l;
        }

    }

    static class IntRangeHash implements RangeHash {
        HashData hd1;
        HashData hd2;
        int[] h1;
        int[] h2;

        public IntRangeHash(HashData hd1, HashData hd2, int n) {
            this.hd1 = hd1;
            this.hd2 = hd2;
            h1 = new int[n + 10];
            h2 = new int[n + 10];
        }

        private void normalize(int i) {
            h1[i] = DigitUtils.mod(h1[i], hd1.mod);
            h2[i] = DigitUtils.mod(h2[i], hd1.mod);
        }

        public void populate(IntToIntegerFunction function, int n) {
            if (n == 0) {
                return;
            }
            h1[0] = h2[0] = function.apply(0);
            normalize(0);
            for (int i = 1; i < n; i++) {
                h1[i] = h2[i] = function.apply(i);
                normalize(i);
                h1[i] = (int) (((long) h1[i] * hd1.pow[i] + h1[i - 1]) % hd1.mod);
                h2[i] = (int) (((long) h2[i] * hd2.pow[i] + h2[i - 1]) % hd2.mod);
            }
        }

        private int hash1(int l, int r) {
            if (l > r) {
                return 0;
            }
            int ans1 = h1[r];
            if (l > 0) {
                ans1 = DigitUtils.modsub(ans1, h1[l - 1], hd1.mod);
                ans1 = (int) ((long) ans1 * hd1.inv[l] % hd1.mod);
            }
            return ans1;
        }

        private int hash2(int l, int r) {
            if (l > r) {
                return 0;
            }
            int ans2 = h2[r];
            if (l > 0) {
                ans2 = DigitUtils.modsub(ans2, h2[l - 1], hd2.mod);
                ans2 = (int) ((long) ans2 * hd2.inv[l] % hd2.mod);
            }
            return ans2;
        }

        public long hash(int l, int r) {
            return DigitUtils.asLong(hash1(l, r), hash2(l, r));
        }

    }

    static class ExtGCD {
        public static int extGCD(int a, int b, int[] xy) {
            if (a >= b) {
                return extGCD0(a, b, xy);
            }
            int ans = extGCD0(b, a, xy);
            SequenceUtils.swap(xy, 0, 1);
            return ans;
        }

        private static int extGCD0(int a, int b, int[] xy) {
            if (b == 0) {
                xy[0] = 1;
                xy[1] = 0;
                return a;
            }
            int ans = extGCD0(b, a % b, xy);
            int x = xy[0];
            int y = xy[1];
            xy[0] = y;
            xy[1] = x - a / b * y;
            return ans;
        }

    }

    static strictfp class MersenneTwisterFast implements Serializable, Cloneable {
        private static final int N = 624;
        private static final int M = 397;
        private static final int MATRIX_A = 0x9908b0df;
        private static final int UPPER_MASK = 0x80000000;
        private static final int LOWER_MASK = 0x7fffffff;
        private static final int TEMPERING_MASK_B = 0x9d2c5680;
        private static final int TEMPERING_MASK_C = 0xefc60000;
        private int[] mt;
        private int mti;
        private int[] mag01;
        private boolean __haveNextNextGaussian;

        public Object clone() {
            try {
                MersenneTwisterFast f = (MersenneTwisterFast) (super.clone());
                f.mt = (int[]) (mt.clone());
                f.mag01 = (int[]) (mag01.clone());
                return f;
            } catch (CloneNotSupportedException e) {
                throw new InternalError();
            } // should never happen
        }

        public MersenneTwisterFast() {
            this(System.currentTimeMillis());
        }

        public MersenneTwisterFast(long seed) {
            setSeed(seed);
        }

        public MersenneTwisterFast(int[] array) {
            setSeed(array);
        }

        public void setSeed(long seed) {
            // Due to a bug in java.util.Random clear up to 1.2, we're
            // doing our own Gaussian variable.
            __haveNextNextGaussian = false;

            mt = new int[N];

            mag01 = new int[2];
            mag01[0] = 0x0;
            mag01[1] = MATRIX_A;

            mt[0] = (int) (seed & 0xffffffff);
            for (mti = 1; mti < N; mti++) {
                mt[mti] =
                        (1812433253 * (mt[mti - 1] ^ (mt[mti - 1] >>> 30)) + mti);
                /* See Knuth TAOCP Vol2. 3rd Ed. P.106 for multiplier. */
                /* In the previous versions, MSBs of the seed affect   */
                /* only MSBs of the array mt[].                        */
                /* 2002/01/09 modified by Makoto Matsumoto             */
                // mt[mti] &= 0xffffffff;
                /* for >32 bit machines */
            }
        }

        public void setSeed(int[] array) {
            if (array.length == 0)
                throw new IllegalArgumentException("Array length must be greater than zero");
            int i, j, k;
            setSeed(19650218);
            i = 1;
            j = 0;
            k = (N > array.length ? N : array.length);
            for (; k != 0; k--) {
                mt[i] = (mt[i] ^ ((mt[i - 1] ^ (mt[i - 1] >>> 30)) * 1664525)) + array[j] + j; /* non linear */
                // mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
                i++;
                j++;
                if (i >= N) {
                    mt[0] = mt[N - 1];
                    i = 1;
                }
                if (j >= array.length) j = 0;
            }
            for (k = N - 1; k != 0; k--) {
                mt[i] = (mt[i] ^ ((mt[i - 1] ^ (mt[i - 1] >>> 30)) * 1566083941)) - i; /* non linear */
                // mt[i] &= 0xffffffff; /* for WORDSIZE > 32 machines */
                i++;
                if (i >= N) {
                    mt[0] = mt[N - 1];
                    i = 1;
                }
            }
            mt[0] = 0x80000000; /* MSB is 1; assuring non-zero initial array */
        }

        public int nextInt(int n) {
            if (n <= 0)
                throw new IllegalArgumentException("n must be positive, got: " + n);

            if ((n & -n) == n)  // i.e., n is a power of 2
            {
                int y;

                if (mti >= N)   // generate N words at one time
                {
                    int kk;
                    final int[] mt = this.mt; // locals are slightly faster
                    final int[] mag01 = this.mag01; // locals are slightly faster

                    for (kk = 0; kk < N - M; kk++) {
                        y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
                        mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
                    }
                    for (; kk < N - 1; kk++) {
                        y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
                        mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
                    }
                    y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
                    mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];

                    mti = 0;
                }

                y = mt[mti++];
                y ^= y >>> 11;                          // TEMPERING_SHIFT_U(y)
                y ^= (y << 7) & TEMPERING_MASK_B;       // TEMPERING_SHIFT_S(y)
                y ^= (y << 15) & TEMPERING_MASK_C;      // TEMPERING_SHIFT_T(y)
                y ^= (y >>> 18);                        // TEMPERING_SHIFT_L(y)

                return (int) ((n * (long) (y >>> 1)) >> 31);
            }

            int bits, val;
            do {
                int y;

                if (mti >= N)   // generate N words at one time
                {
                    int kk;
                    final int[] mt = this.mt; // locals are slightly faster
                    final int[] mag01 = this.mag01; // locals are slightly faster

                    for (kk = 0; kk < N - M; kk++) {
                        y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
                        mt[kk] = mt[kk + M] ^ (y >>> 1) ^ mag01[y & 0x1];
                    }
                    for (; kk < N - 1; kk++) {
                        y = (mt[kk] & UPPER_MASK) | (mt[kk + 1] & LOWER_MASK);
                        mt[kk] = mt[kk + (M - N)] ^ (y >>> 1) ^ mag01[y & 0x1];
                    }
                    y = (mt[N - 1] & UPPER_MASK) | (mt[0] & LOWER_MASK);
                    mt[N - 1] = mt[M - 1] ^ (y >>> 1) ^ mag01[y & 0x1];

                    mti = 0;
                }

                y = mt[mti++];
                y ^= y >>> 11;                          // TEMPERING_SHIFT_U(y)
                y ^= (y << 7) & TEMPERING_MASK_B;       // TEMPERING_SHIFT_S(y)
                y ^= (y << 15) & TEMPERING_MASK_C;      // TEMPERING_SHIFT_T(y)
                y ^= (y >>> 18);                        // TEMPERING_SHIFT_L(y)

                bits = (y >>> 1);
                val = bits % n;
            } while (bits - val + (n - 1) < 0);
            return val;
        }

    }

    static class HashData {
        public int mod;
        public int[] inv;
        public int[] pow;
        public int x;

        public HashData(int n, int p, int x) {
            this.mod = p;
            this.x = x;
            inv = new int[n + 10];
            pow = new int[n + 10];
            inv[0] = 1;
            pow[0] = 1;
            int invX = new Power(p).inverse(x);
            for (int i = 1; i < n + 10; i++) {
                inv[i] = (int) ((long) inv[i - 1] * invX % mod);
                pow[i] = (int) ((long) pow[i - 1] * x % mod);
            }
        }

        public HashData(int n) {
            this(n, (int) 1e9 + 7, RandomWrapper.INSTANCE.nextInt(3, (int) 1e9 + 6));
        }

    }

    static interface LongIterator {
        boolean hasNext();

        long next();

    }

    static class FastOutput implements AutoCloseable, Closeable, Appendable {
        private static final int THRESHOLD = 1 << 13;
        private final Writer os;
        private StringBuilder cache = new StringBuilder(THRESHOLD * 2);

        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;
        }

        private void afterWrite() {
            if (cache.length() < THRESHOLD) {
                return;
            }
            flush();
        }

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

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

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

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

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

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

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

        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();
        }

    }

    static class DigitUtils {
        private static long LONG_TO_INT_MASK = (1L << 32) - 1;

        private DigitUtils() {
        }

        public static long asLong(int high, int low) {
            return (((long) high) << 32) | (((long) low) & LONG_TO_INT_MASK);
        }

        public static int mod(long x, int mod) {
            if (x < -mod || x >= mod) {
                x %= mod;
            }
            if (x < 0) {
                x += mod;
            }
            return (int) x;
        }

        public static int mod(int x, int mod) {
            if (x < -mod || x >= mod) {
                x %= mod;
            }
            if (x < 0) {
                x += mod;
            }
            return x;
        }

        public static int modsub(int a, int b, int mod) {
            int ans = a - b;
            if (ans < 0) {
                ans += mod;
            }
            return ans;
        }

    }

    static class ModifiableHash {
        HashData hd1;
        HashData hd2;
        int h1;
        int h2;
        int[] data;

        public ModifiableHash(HashData hd1, HashData hd2, int n) {
            this.hd1 = hd1;
            this.hd2 = hd2;
            this.data = new int[n + 10];
            this.data = new int[n + 10];
        }

        public void init(int n) {
            h1 = h2 = 0;
            Arrays.fill(data, 0, n, 0);
        }

        public int get(int i) {
            return data[i];
        }

        public long hash() {
            return DigitUtils.asLong(h1, h2);
        }

        public void set(int i, int x) {
            h1 = DigitUtils.mod(h1 + (long) (x - data[i]) * hd1.pow[i], hd1.mod);
            h2 = DigitUtils.mod(h2 + (long) (x - data[i]) * hd2.pow[i], hd2.mod);
            data[i] = x;
        }

        public String toString() {
            return Arrays.toString(data);
        }

    }

    static class Hasher {
        private long time = System.nanoTime() + System.currentTimeMillis() * 31L;

        public int shuffle(long z) {
            z += time;
            z = (z ^ (z >>> 33)) * 0x62a9d9ed799705f5L;
            return (int) (((z ^ (z >>> 28)) * 0xcb24d0a5c88c35b3L) >>> 32);
        }

        public int hash(long x) {
            return shuffle(x);
        }

    }

    static interface InverseNumber {
    }

    static class SequenceUtils {
        public static void swap(int[] data, int i, int j) {
            int tmp = data[i];
            data[i] = data[j];
            data[j] = tmp;
        }

    }

    static class LongHashSet {
        private int now;
        private int[] slot;
        private int[] version;
        private int[] next;
        private long[] keys;
        private int alloc;
        private boolean[] removed;
        private int mask;
        private int size;
        private boolean rehash;
        private Hasher hasher = new Hasher();

        public LongHashSet(int cap, boolean rehash) {
            now = 1;
            this.mask = (1 << (32 - Integer.numberOfLeadingZeros(cap - 1))) - 1;
            this.rehash = rehash;
            slot = new int[mask + 1];
            version = new int[slot.length + 1];
            next = new int[cap + 1];
            keys = new long[cap + 1];
            removed = new boolean[cap + 1];
        }

        private void access(int i) {
            if (version[i] != now) {
                version[i] = now;
                slot[i] = 0;
            }
        }

        private void doubleCapacity() {
            int newSize = Math.max(next.length + 10, next.length * 2);
            next = Arrays.copyOf(next, newSize);
            keys = Arrays.copyOf(keys, newSize);
            removed = Arrays.copyOf(removed, newSize);
        }

        public void alloc() {
            alloc++;
            if (alloc >= next.length) {
                doubleCapacity();
            }
            next[alloc] = 0;
            removed[alloc] = false;
            size++;
        }

        private int hash(long x) {
            return hasher.hash(x);
        }

        public void add(long x) {
            int h = hash(x);
            int s = h & mask;
            access(s);
            if (slot[s] == 0) {
                alloc();
                slot[s] = alloc;
                keys[alloc] = x;
                return;
            } else {
                int index = findIndexOrLastEntry(s, x);
                if (keys[index] != x) {
                    alloc();
                    next[index] = alloc;
                    keys[alloc] = x;
                }
            }
            if (rehash && size >= slot.length) {
                rehash();
            }
        }

        private void rehash() {
            int[] newSlots = new int[Math.max(16, slot.length * 2)];
            int[] newVersions = new int[newSlots.length];
            int newMask = newSlots.length - 1;
            for (int i = 0; i < slot.length; i++) {
                access(i);
                if (slot[i] == 0) {
                    continue;
                }
                int head = slot[i];
                while (head != 0) {
                    int n = next[head];
                    int s = hash(keys[head]) & newMask;
                    next[head] = newSlots[s];
                    newSlots[s] = head;
                    head = n;
                }
            }
            this.slot = newSlots;
            this.version = newVersions;
            now = 0;
            this.mask = newMask;
        }

        public boolean contain(long x) {
            int h = hash(x);
            int s = h & mask;
            access(s);
            if (slot[s] == 0) {
                return false;
            }
            return keys[findIndexOrLastEntry(s, x)] == x;
        }

        private int findIndexOrLastEntry(int s, long x) {
            int iter = slot[s];
            while (keys[iter] != x) {
                if (next[iter] != 0) {
                    iter = next[iter];
                } else {
                    return iter;
                }
            }
            return iter;
        }

        public void clear() {
            alloc = 0;
            size = 0;
            now++;
        }

        public LongIterator iterator() {
            return new LongIterator() {
                int index = 1;


                public boolean hasNext() {
                    while (index <= alloc && removed[index]) {
                        index++;
                    }
                    return index <= alloc;
                }


                public long next() {
                    if (!hasNext()) {
                        throw new IllegalStateException();
                    }
                    return keys[index++];
                }
            };
        }

        public String toString() {
            LongIterator iterator = iterator();
            StringBuilder builder = new StringBuilder("{");
            while (iterator.hasNext()) {
                builder.append(iterator.next()).append(',');
            }
            if (builder.charAt(builder.length() - 1) == ',') {
                builder.setLength(builder.length() - 1);
            }
            builder.append('}');
            return builder.toString();
        }

    }

    static class Modular {
        int m;

        public int getMod() {
            return m;
        }

        public Modular(int m) {
            this.m = m;
        }

        public Modular(long m) {
            this.m = (int) m;
            if (this.m != m) {
                throw new IllegalArgumentException();
            }
        }

        public Modular(double m) {
            this.m = (int) m;
            if (this.m != m) {
                throw new IllegalArgumentException();
            }
        }

        public String toString() {
            return "mod " + m;
        }

    }

    static class IntExtGCDObject {
        private int[] xy = new int[2];

        public int extgcd(int a, int b) {
            return ExtGCD.extGCD(a, b, xy);
        }

        public int getX() {
            return xy[0];
        }

    }

    static interface IntToIntegerFunction {
        int apply(int x);

    }

    static class Power implements InverseNumber {
        static IntExtGCDObject extGCD = new IntExtGCDObject();
        int mod;

        public Power(Modular modular) {
            this.mod = modular.getMod();
        }

        public Power(int mod) {
            this(new Modular(mod));
        }

        public int inverse(int x) {
            int ans = inverseExtGCD(x);
//        if(modular.mul(ans, x) != 1){
//            throw new IllegalStateException();
//        }
            return ans;
        }

        public int inverseExtGCD(int x) {
            if (extGCD.extgcd(x, mod) != 1) {
                throw new IllegalArgumentException();
            }
            return DigitUtils.mod(extGCD.getX(), mod);
        }

    }

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

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

        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 String next() {
            return readString();
        }

        public int ri() {
            return readInt();
        }

        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;
        }

        public char rc() {
            return readChar();
        }

        public char readChar() {
            skipBlank();
            char c = (char) next;
            next = read();
            return c;
        }

        public String readString(StringBuilder builder) {
            skipBlank();

            while (next > 32) {
                builder.append((char) next);
                next = read();
            }

            return builder.toString();
        }

        public String readString() {
            defaultStringBuf.setLength(0);
            return readString(defaultStringBuf);
        }

    }
}