dsets.cpp

/**
*  Class implementation of Disjoint sets
*/

#include "dsets.h"

void DisjointSets::addelements(int num)
{
    for (int i = 0; i < num; i++)
    {
        array.push_back(-1);
    }
}

int DisjointSets::find(int elem)
{
    if(array[elem] < 0)
    {
        return elem;
    }
    else
    {
        return(array[elem] = find(array[elem]));
    }
}

void DisjointSets::setunion( int a, int b )
{
    int root_a=find(a);
    int root_b=find(b);
    if(root_a!=root_b)
    {
        if((-1)*array[root_a]<(-1)*array[root_b])
        {
            array[root_b]+=array[root_a];
            array[root_a]=root_b;
        }
        else
        {
            array[root_a]+=array[root_b];
            array[root_b]=root_a;
        }
    }
}