@Override
public int nextSetBit(int i) {
assert i <= size();
if (i < Long.SIZE) {
long maskedWord = word0 & (WORD_MASK << i);
if (maskedWord != 0) {
return Long.numberOfTrailingZeros(maskedWord);
}
i = Long.SIZE;
}
i -= Long.SIZE;
if (i < Long.SIZE) {
long maskedWord = word1 & (WORD_MASK << i);
if (maskedWord != 0) {
return Long.numberOfTrailingZeros(maskedWord) + Long.SIZE;
}
i = Long.SIZE;
}
i -= Long.SIZE;
if (i < Long.SIZE) {
long maskedWord = word2 & (WORD_MASK << i);
if (maskedWord != 0) {
return Long.numberOfTrailingZeros(maskedWord) + 2 * Long.SIZE;
}
i = Long.SIZE;
}
i -= Long.SIZE;
long maskedWord = word3 & (WORD_MASK << i);
return maskedWord == 0 ? -1 : Long.numberOfTrailingZeros(maskedWord) + 3 * Long.SIZE;
}
// Shifts long bits as double, if the digits is positive, left-shift; if
// not, shift to right and calculate its carry.
private static long shiftLongBits(long bits, long digits) {
if (digits > 0) {
return bits << digits;
}
// change it to positive
long absdigits = -digits;
if (!(Long.numberOfLeadingZeros(bits & ~DOUBLE_SIGN_MASK) <= (64 - absdigits))) {
return 0;
}
long ret = bits >> absdigits;
boolean halfbit = ((bits >> (absdigits - 1)) & 0x1) == 1;
if (halfbit) {
// some bits will remain after shifting, calculates its carry
// subnormal
if (Long.numberOfTrailingZeros(bits) < (absdigits - 1)) {
ret = ret + 1;
}
if (Long.numberOfTrailingZeros(bits) == (absdigits - 1)) {
if ((ret & 0x1) == 1) {
ret = ret + 1;
}
}
}
return ret;
}
@Override
public int nextSetBit(int i) {
assert i < length;
final int i4096 = i >>> 12;
final long index = indices[i4096];
final long[] bitArray = this.bits[i4096];
int i64 = i >>> 6;
int o = Long.bitCount(index & ((1L << i64) - 1));
if ((index & (1L << i64)) != 0) {
// There is at least one bit that is set in the current long, check if
// one of them is after i
final long bits = bitArray[o] >>> i; // shifts are mod 64
if (bits != 0) {
return i + Long.numberOfTrailingZeros(bits);
}
o += 1;
}
final long indexBits = index >>> i64 >>> 1;
if (indexBits == 0) {
// no more bits are set in the current block of 4096 bits, go to the next one
return firstDoc(i4096 + 1);
}
// there are still set bits
i64 += 1 + Long.numberOfTrailingZeros(indexBits);
final long bits = bitArray[o];
return (i64 << 6) | Long.numberOfTrailingZeros(bits);
}
/**
* Returns {@code n!}, that is, the product of the first {@code n} positive integers, or {@code 1}
* if {@code n == 0}.
*
* <p><b>Warning:</b> the result takes <i>O(n log n)</i> space, so use cautiously.
*
* <p>This uses an efficient binary recursive algorithm to compute the factorial with balanced
* multiplies. It also removes all the 2s from the intermediate products (shifting them back in at
* the end).
*
* @throws IllegalArgumentException if {@code n < 0}
*/
public static BigInteger factorial(int n) {
checkNonNegative("n", n);
// If the factorial is small enough, just use LongMath to do it.
if (n < LongMath.factorials.length) {
return BigInteger.valueOf(LongMath.factorials[n]);
}
// Pre-allocate space for our list of intermediate BigIntegers.
int approxSize = IntMath.divide(n * IntMath.log2(n, CEILING), Long.SIZE, CEILING);
ArrayList<BigInteger> bignums = new ArrayList<BigInteger>(approxSize);
// Start from the pre-computed maximum long factorial.
int startingNumber = LongMath.factorials.length;
long product = LongMath.factorials[startingNumber - 1];
// Strip off 2s from this value.
int shift = Long.numberOfTrailingZeros(product);
product >>= shift;
// Use floor(log2(num)) + 1 to prevent overflow of multiplication.
int productBits = LongMath.log2(product, FLOOR) + 1;
int bits = LongMath.log2(startingNumber, FLOOR) + 1;
// Check for the next power of two boundary, to save us a CLZ operation.
int nextPowerOfTwo = 1 << (bits - 1);
// Iteratively multiply the longs as big as they can go.
for (long num = startingNumber; num <= n; num++) {
// Check to see if the floor(log2(num)) + 1 has changed.
if ((num & nextPowerOfTwo) != 0) {
nextPowerOfTwo <<= 1;
bits++;
}
// Get rid of the 2s in num.
int tz = Long.numberOfTrailingZeros(num);
long normalizedNum = num >> tz;
shift += tz;
// Adjust floor(log2(num)) + 1.
int normalizedBits = bits - tz;
// If it won't fit in a long, then we store off the intermediate product.
if (normalizedBits + productBits >= Long.SIZE) {
bignums.add(BigInteger.valueOf(product));
product = 1;
productBits = 0;
}
product *= normalizedNum;
productBits = LongMath.log2(product, FLOOR) + 1;
}
// Check for leftovers.
if (product > 1) {
bignums.add(BigInteger.valueOf(product));
}
// Efficiently multiply all the intermediate products together.
return listProduct(bignums).shiftLeft(shift);
}
/** Return the first document that occurs on or after the provided block index. */
private int firstDoc(int i4096) {
long index = 0;
while (i4096 < indices.length) {
index = indices[i4096];
if (index != 0) {
final int i64 = Long.numberOfTrailingZeros(index);
return (i4096 << 12) | (i64 << 6) | Long.numberOfTrailingZeros(bits[i4096][0]);
}
i4096 += 1;
}
return DocIdSetIterator.NO_MORE_DOCS;
}
/**
* Find the index of the next set bit greater or equal to i, returns -1 if none found.
*
* @param i starting index
* @return index of the next set bit
*/
public int nextSetBit(final int i) {
int x = i >> 6; // i / 64 with sign extension
long w = bitmap[x];
w >>>= i;
if (w != 0) {
return i + Long.numberOfTrailingZeros(w);
}
for (++x; x < bitmap.length; ++x) {
if (bitmap[x] != 0) {
return x * 64 + Long.numberOfTrailingZeros(bitmap[x]);
}
}
return -1;
}
/**
* Find the index of the next unset bit greater or equal to i, returns -1 if none found.
*
* @param i starting index
* @return index of the next unset bit
*/
public short nextUnsetBit(final int i) {
int x = i / 64;
long w = ~bitmap[x];
w >>>= i;
if (w != 0) {
return (short) (i + Long.numberOfTrailingZeros(w));
}
++x;
for (; x < bitmap.length; ++x) {
if (bitmap[x] != ~0L) {
return (short) (x * 64 + Long.numberOfTrailingZeros(~bitmap[x]));
}
}
return -1;
}
@Override
public long nextClearBit(long fromIndex) {
if (fromIndex < 0) throw new IndexOutOfBoundsException();
long fromLongIndex = fromIndex >> 6;
if (fromLongIndex >= longLength) return NOT_FOUND;
long l = (~bytes.readLong(fromLongIndex << 3)) >>> fromIndex;
if (l != 0) {
return fromIndex + Long.numberOfTrailingZeros(l);
}
for (long i = fromLongIndex + 1; i < longLength; i++) {
l = ~bytes.readLong(i << 3);
if (l != 0) return (i << 6) + Long.numberOfTrailingZeros(l);
}
return NOT_FOUND;
}
public static boolean isValidWildcard(Ip wildcard) {
long w = wildcard.asLong();
long wp = w + 1l;
int numTrailingZeros = Long.numberOfTrailingZeros(wp);
long check = 1l << numTrailingZeros;
return wp == check;
}
public E next() {
if (!hasNext()) throw new NoSuchElementException();
lastReturned = unseen & -unseen;
lastReturnedIndex = unseenIndex;
unseen -= lastReturned;
return (E) universe[(lastReturnedIndex << 6) + Long.numberOfTrailingZeros(lastReturned)];
}
/** Writes a right-zero-extended value to {@code out}. */
public static void writeRightZeroExtendedValue(ByteOutput out, int type, long value) {
// Figure out how many bits are needed to represent the value.
int requiredBits = 64 - Long.numberOfTrailingZeros(value);
if (requiredBits == 0) {
requiredBits = 1;
}
// Round up the requiredBits to a number of bytes.
int requiredBytes = (requiredBits + 0x07) >> 3;
// Scootch the first bits to be written down to the low-order bits.
value >>= 64 - (requiredBytes * 8);
/*
* Write the header byte, which includes the type and
* requiredBytes - 1.
*/
out.writeByte(type | ((requiredBytes - 1) << 5));
// Write the value, per se.
while (requiredBytes > 0) {
out.writeByte((byte) value);
value >>= 8;
requiredBytes--;
}
}
private int addThread() {
boolean set;
int n;
do {
long l = bits.longValue();
long next = (l + 1) | l;
n = Long.numberOfTrailingZeros(l + 1);
set = bits.compareAndSet(l, next);
} while (!set);
return n;
}
private void scoreMatches(LeafCollector collector, int base) throws IOException {
long matching[] = this.matching;
for (int idx = 0; idx < matching.length; idx++) {
long bits = matching[idx];
while (bits != 0L) {
int ntz = Long.numberOfTrailingZeros(bits);
int doc = idx << 6 | ntz;
scoreDocument(collector, base, doc);
bits ^= 1L << ntz;
}
}
}
/**
* Returns the index of the first bit that is set to <code>true</code> that occurs on or after the
* specified starting index. If no such bit exists then -1 is returned.
*
* <p>To iterate over the <code>true</code> bits in a <code>BitSet</code>, use the following loop:
*
* <p>
*
* <pre>
* for (int i = bs.nextSetBit(0); i >= 0; i = bs.nextSetBit(i+1)) {
* // operate on index i here
* }</pre>
*
* @param fromIndex the index to start checking from (inclusive).
* @return the index of the next set bit.
* @throws IndexOutOfBoundsException if the specified index is negative.
*/
public int nextSetBit(int fromIndex) {
if (fromIndex < 0) throw new IndexOutOfBoundsException("fromIndex: " + fromIndex);
if (fromIndex >= size) return -1;
int u = wordIndex(fromIndex);
long word = words[u] & (WORD_MASK << fromIndex);
while (true) {
if (word != 0) return (u * BITS_PER_WORD) + Long.numberOfTrailingZeros(word);
if (++u == words.length) return -1;
word = words[u];
}
}
public E next() {
if (mask == 0) {
throw new NoSuchElementException();
}
int ordinal = Long.numberOfTrailingZeros(mask) + index * BIT_IN_LONG;
last = enums[ordinal];
currentBits &= ~mask;
computeNextElement();
return last;
}
/** @return true if the estimation was affected by this addition */
public boolean add(long value) {
BucketAndHash bucketAndHash = fromHash(computeHash(value), estimator.getNumberOfBuckets());
int lowestBitPosition = Long.numberOfTrailingZeros(bucketAndHash.getHash()) + 1;
if (estimator.getClass() == SparseEstimator.class
&& (estimator.estimateSizeInBytes()
>= DenseEstimator.estimateSizeInBytes(estimator.getNumberOfBuckets())
|| lowestBitPosition >= SparseEstimator.MAX_BUCKET_VALUE)) {
estimator = new DenseEstimator(estimator.buckets());
}
return estimator.setIfGreater(bucketAndHash.getBucket(), lowestBitPosition);
}
public static String print(long bitmap) {
StringBuilder sb = new StringBuilder(ZEROS);
while (bitmap != 0) {
long bit = Long.lowestOneBit(bitmap);
int pos = Long.numberOfTrailingZeros(bit);
sb.replace(63 - pos, 64 - pos, "1");
bitmap &= ~bit;
}
for (int x = 0; x < 7; x++) {
sb.insert(8 + (9 * x), "_");
}
sb.insert(0, "0b").append("L");
return sb.toString();
}
private static IntArray toIndexArray(long[] supportA, long[] supportB, IntArray indices) {
if (indices == null) {
indices = new IntArray();
} else {
indices.clear();
}
for (int i = 0; i < supportA.length; i++) {
long commonSupport = supportA[i] & supportB[i];
while (commonSupport != 0) {
final int index = Long.numberOfTrailingZeros(commonSupport);
indices.add(index + i * 64);
commonSupport ^= (1L << index);
}
}
return indices;
}
/**
* Returns the index of the first bit that is set to <code>false</code> that occurs on or after
* the specified starting index.
*
* @param fromIndex the index to start checking from (inclusive).
* @return the index of the next clear bit.
* @throws IndexOutOfBoundsException if the specified index is negative.
*/
public int nextClearBit(int fromIndex) {
// Neither spec nor implementation handle bitsets of maximal length.
// See 4816253.
if (fromIndex < 0) throw new IndexOutOfBoundsException("fromIndex: " + fromIndex);
if (fromIndex >= size) return -1;
int u = wordIndex(fromIndex);
if (u >= words.length) return fromIndex;
long word = ~words[u] & (WORD_MASK << fromIndex);
while (true) {
if (word != 0) return (u * BITS_PER_WORD) + Long.numberOfTrailingZeros(word);
if (++u == words.length) return -1;
word = ~words[u];
}
}
private static int nextSetBit(int bitIndex, int[] bits, int bitsLength) {
int wordIndex = bitIndex >> INT_BITS_SHIFT;
if (wordIndex >= bitsLength) {
return -1;
}
int word = bits[wordIndex] & (-1 << bitIndex);
while (true) {
if (word != 0) {
return (wordIndex << INT_BITS_SHIFT) + Long.numberOfTrailingZeros(word);
}
if (++wordIndex == bitsLength) {
return -1;
}
word = bits[wordIndex];
}
}
public long get(int index) {
long highBit = skipIndex[(index >>> 7) * 2];
long previousValue = skipIndex[((index >>> 7) * 2) + 1];
long highBitValue = previousValue >> numLowBits;
int currentHighBitLongIndex = (int) (highBit >>> 6);
int currentHighBitBitIndex = (int) (highBit & 0x3F);
int numBitsToRead = index & 0x7F;
long curVal = highBits.get(currentHighBitLongIndex);
curVal >>>= currentHighBitBitIndex;
int bitCount = Long.bitCount(curVal);
while (numBitsToRead >= bitCount) {
highBitValue += 64 - currentHighBitBitIndex - bitCount;
numBitsToRead -= bitCount;
currentHighBitBitIndex = 0;
currentHighBitLongIndex++;
curVal = highBits.get(currentHighBitLongIndex);
bitCount = Long.bitCount(curVal);
}
int encodedHighBitValue = 0;
for (int i = 0; i <= numBitsToRead; i++) {
encodedHighBitValue = Long.numberOfTrailingZeros(curVal);
highBitValue += encodedHighBitValue;
curVal >>>= encodedHighBitValue + 1;
}
long lowBitData = getLowBits(index);
if (lowBitData == 0
&& encodedHighBitValue == 0
&& (numBitsToRead != 0
|| currentHighBitBitIndex != 0
|| (currentHighBitLongIndex == 0 || highBits.get(currentHighBitLongIndex - 1) < 0))) {
return -1;
}
return (highBitValue << numLowBits) | lowBitData;
}
public void add(long value) {
BucketAndHash bucketAndHash = BucketAndHash.fromHash(computeHash(value), buckets.length);
int bucket = bucketAndHash.getBucket();
int lowestBitPosition = Long.numberOfTrailingZeros(bucketAndHash.getHash()) + 1;
int previous = buckets[bucket];
if (previous == 0) {
nonZeroBuckets++;
}
if (lowestBitPosition > previous) {
currentSum -= 1.0 / (1L << previous);
currentSum += 1.0 / (1L << lowestBitPosition);
buckets[bucket] = (byte) lowestBitPosition;
}
}
/**
* Constructs a HilbertCurve with the specified dimension count and side length
*
* @param dimension the number of dimensions to use, all with equal length; must be between 2 and
* 31
* @param sideLength the length of a side, which will be rounded up to the next-higher power of
* two if it isn't already a power of two. sideLength ^ dimension must be less than 2^31.
*/
public HilbertCurve(int dimension, int sideLength) {
if (dimension > 31) dimension = 31;
dims = dimension;
if (sideLength <= 1) {
sideLength = 2;
}
side = HilbertUtility.nextPowerOfTwo(sideLength);
bits = Long.numberOfTrailingZeros(side);
if (bits * dims >= 31) {
bits = 31 / dims;
side = 1 << bits;
}
dimensionality = new int[dims];
offsets = new int[dims];
Arrays.fill(dimensionality, side);
maxDistance = 1 << (bits * dims);
}
@Override
public BoardSquare next() {
prev = unseen & -unseen;
unseen -= prev;
return BoardSquare.values()[Long.numberOfTrailingZeros(prev)];
}
/**
* @return 1-indexed alloc index, to allow {@code slot != 0} conditions, i. e. allocIndex = 0
* means empty hash table slot
*/
final long alloc() {
long bitSet = this.bitSet;
this.bitSet = (bitSet - 1) & bitSet;
return Long.numberOfTrailingZeros(bitSet) + 1;
}
