并查集C++源码

一、UniteFind.h源码

#pragma once
#include "stdafx.h"
class UniteFind
{
private :
    int* nodeRoot;
    int* treeHeight;
    int nodeNum;
    int findRoot(int node)
    {
        while (nodeRoot[node] != node)
        {
            node = nodeRoot[node];
        } 
        return node;
    }
public:
    UniteFind(int n)
    {
        nodeRoot = new int[n];
        treeHeight = new int[n];
        for(int i=0; i<n; i++)
        {
            nodeRoot[i] = i; //每个节点的树根是自己
            treeHeight[i] = 0;
        }
        nodeNum = n;
    }
    ~UniteFind()
    {
        delete[] nodeRoot;
        delete[] treeHeight;
        nodeRoot = nullptr;
        treeHeight = nullptr;
    }
    void unite(int a, int b)
    {
        if(a==b || a <0 || a>=nodeNum || b <0 || b>=nodeNum)
        {
            return;
        }
        int aRoot = findRoot(a);
        int bRoot = findRoot(b);
        //根据树的高度，将高度低的树根的父节点设置成高度高的树根
        if(treeHeight[aRoot] < treeHeight[bRoot])
        {
            nodeRoot[aRoot] = bRoot;
        }
        else
        {
            nodeRoot[bRoot] = aRoot;
            if(treeHeight[aRoot] == treeHeight[bRoot])
            {
                aRoot++;
            }
        }
    }
    bool isOneUnite(int a, int b)
    {
        if(a==b || a <0 || a>=nodeNum || b <0 || b>=nodeNum)
        {
            return false;
        }
        return findRoot(a) == findRoot(b);
    }
    int getUniteNum()
    {
        int num = 0;
        for(int i=0;i<nodeNum; i++)
        {
            if(nodeRoot[i] == i)
            {
                num++;
            }
        }
        return num;
    }
};

二、UniteFindTest.h源码

#pragma  once
#include "stdafx.h"
#include "UniteFind.h"
class UniteFindTest
{
public:
    void doTest()
    {
        UniteFind unitFind(10);
        unitFind.unite(0,3);
        unitFind.unite(2,4);
        unitFind.unite(2,3);
        unitFind.unite(5,7);
        unitFind.unite(6,8);
        unitFind.unite(9,6);
        cout << (unitFind.isOneUnite(2,0)?"true":"false") <<endl;
        cout << (unitFind.isOneUnite(3,5)?"true":"false") <<endl;
        cout << unitFind.getUniteNum() << endl;
    }
};