com.exigen.ie.constrainer.IntVarSelectorMinMin Maven / Gradle / Ivy
package com.exigen.ie.constrainer;
///////////////////////////////////////////////////////////////////////////////
/*
* Copyright Exigen Group 1998, 1999, 2000, 2002
* 320 Amboy Ave., Metuchen, NJ, 08840, USA, www.exigengroup.com
*
* The copyright to the computer program(s) herein
* is the property of Exigen Group, USA. All rights reserved.
* The program(s) may be used and/or copied only with
* the written permission of Exigen Group
* or in accordance with the terms and conditions
* stipulated in the agreement/contract under which
* the program(s) have been supplied.
*/
///////////////////////////////////////////////////////////////////////////////
/**
* An implementation of the IntVarSelector interface
* that selects the unbound variable with the minimal minimum.
*
* @see IntVarSelector
* @see IntVarSelectorFirstUnbound
* @see IntVarSelectorMinSize
* @see GoalGenerate
*/
public class IntVarSelectorMinMin implements IntVarSelector
{
private IntExpArray _intvars;
/**
* Constructor from the IntExpArray.
*/
public IntVarSelectorMinMin(IntExpArray intvars)
{
_intvars = intvars;
}
/**
* Selects the unbound variable with the smallest domain.
* If there are two variables with the same size,
* it will select the variable with the minimal minimum.
* If all variables are bound, returns -1.
*/
public int select()
{
int max_size = -1;
int min_min = Integer.MAX_VALUE;
int min_index = -1;
int size = _intvars.size();
for(int i=0; i < size; i++)
{
IntVar vari = (IntVar)_intvars.elementAt(i);
if (!vari.bound())
{
if (min_index==-1 || min_min >= vari.min())
{
if (min_min > vari.min())// || max_size < vari.size())
{
max_size = vari.size();
min_min = vari.min();
min_index = i;
}
}
}
}
return min_index;
}
} // ~IntVarSelectorMinMin