it.unimi.dsi.sux4j.bits
Class Select9

java.lang.Object
  it.unimi.dsi.sux4j.bits.Select9

All Implemented Interfaces:

Select, Serializable

public class Select9
extends Object
implements Select

A select9 implementation.

select9 is based on an underlying rank9 instance and uses 25%-37.5% additional space (beside the 25% due to rank9), depending on density. It guarantees practical constant time evaluation.

See Also:

Serialized Form

Constructor Summary

Select9(Rank9 rank9)

Method Summary

BitVector	bitVector() Returns the bit vector indexed by this structure.
long	numBits() Returns the overall number of bits allocated by this structure.
long	select(long rank) Returns the position of the bit of given rank.

Methods inherited from class java.lang.Object

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

Constructor Detail

Select9

public Select9(Rank9 rank9)

Method Detail

select

public long select(long rank)

Description copied from interface: Select

Returns the position of the bit of given rank. Equivalently, returns the greatest position that is preceded by the specified number of ones.

Specified by:

select in interface Select

Parameters:

rank - a rank.

Returns:

the position of the bit of given rank; if no such position exists, −1 is returned.

numBits

public long numBits()

Description copied from interface: Select

Returns the overall number of bits allocated by this structure.

Specified by:

numBits in interface Select

Returns:

the overall number of bits allocated by this structure (not including the bits of the indexed vector).

bitVector

public BitVector bitVector()

Description copied from interface: Select

Returns the bit vector indexed by this structure.

Note that you are not supposed to modify the returned vector.

Specified by:

bitVector in interface Select

Returns:

the bit vector indexed by this structure.