UnionFindTestHelper.h

#ifndef INC_02_QUICK_FIND_UNIONFINDTESTHELPER_H
#define INC_02_QUICK_FIND_UNIONFINDTESTHELPER_H

#include <iostream>
#include <ctime>
#include "UnionFind1.h"

using namespace std;

namespace UnionFindTestHelper{

    void testUF1( int n ){

        srand( time(NULL) );
        UF1::UnionFind uf = UF1::UnionFind(n);

        time_t startTime = clock();

        for( int i = 0 ; i < n ; i ++ ){
            int a = rand()%n;
            int b = rand()%n;
            uf.unionElements(a,b);
        }
        for(int i = 0 ; i < n ; i ++ ){
            int a = rand()%n;
            int b = rand()%n;
            uf.isConnected(a,b);
        }
        time_t endTime = clock();

        cout<<"UF1, "<<2*n<<" ops, "<<double(endTime-startTime)/CLOCKS_PER_SEC<<" s"<<endl;
    }
}
#endif

UnionFind.h

#ifndef INC_02_QUICK_FIND_UNIONFIND1_H
#define INC_02_QUICK_FIND_UNIONFIND1_H

#include <iostream>
#include <cassert>

using namespace std;

namespace UF1 {

    class UnionFind {

    private:
        int *id;
        int count;

    public:
        UnionFind(int n) {
            count = n;
            id = new int[n];
            for (int i = 0; i < n; i++)
                id[i] = i;
        }

        ~UnionFind() {
            delete[] id;
        }

        int find(int p) {
            assert(p >= 0 && p < count);
            return id[p];
        }

        bool isConnected(int p, int q) {
            return find(p) == find(q);
        }

        void unionElements(int p, int q) {

            int pID = find(p);
            int qID = find(q);

            if (pID == qID)
                return;

            for (int i = 0; i < count; i++)
                if (id[i] == pID)
                    id[i] = qID;
        }
    };
}
#endif

main.cpp

#include <iostream>
#include "UnionFindTestHelper.h"

using namespace std;


int main() {

    int n = 10000;

    UnionFindTestHelper::testUF1(n);

    return 0;
}