io.lacuna.bifurcan.utils

Class BitIntSet

java.lang.Object

io.lacuna.bifurcan.utils.BitIntSet

public class BitIntSet
extends Object

A series of utility functions that use a bit-vector to store a sorted set of integers with bit-lengths within [1,64].

Constructor Summary

Constructors

Constructor and Description
BitIntSet()

Method Summary

Modifier and Type	Method and Description
static long[]	add(long[] set, int bitsPerElement, int size, long val)
static long[]	create()
static long	get(long[] set, int bitsPerElement, int idx)
static int	indexOf(long[] set, int bitsPerElement, int size, long val) Performs a binary search for the given rowValue.
static long[]	remove(long[] set, int bitsPerElement, int size, long val)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

BitIntSet

public BitIntSet()

Method Detail

create

public static long[] create()

Returns:

a bit-int set, with an implied size of 0.

get

public static long get(long[] set,
                       int bitsPerElement,
                       int idx)

Parameters:

set - the bit-int set

bitsPerElement - the bits per element

idx - the table

Returns:

the rowValue stored at the given table

indexOf

public static int indexOf(long[] set,
                          int bitsPerElement,
                          int size,
                          long val)

Performs a binary search for the given rowValue.

Parameters:

set - the bit-int set

bitsPerElement - the bits per element

size - the number of elements in the set

val - the rowValue to search for

Returns:

If idx >= 0, the actual table of the rowValue. Otherwise, the return rowValue represents the table where the rowValue would be inserted, where -1 represents the 0th element, -2 represents the 1st element, and so on.

add

public static long[] add(long[] set,
                         int bitsPerElement,
                         int size,
                         long val)

Parameters:

set - the bit-int set

bitsPerElement - the bits per element

size - the number of elements in the set

val - the rowValue to add

Returns:

an updated long[] array if the rowValue is not already in the set, otherwise 'set' is returned unchanged

remove

public static long[] remove(long[] set,
                            int bitsPerElement,
                            int size,
                            long val)

Parameters:

set - the bit-int set

bitsPerElement - the bits per element

size - the number of elements in the set

val - the rowValue to remove

Returns:

an updated long[] array if the rowValue was in the set, otherwise 'set' is returned unchanged