UVA 10600 / 2nd best MST

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define test int tt; cin>>tt; for(int cs=1;cs<=tt;cs++)

vector<ll>parent,rankk;
map<pair<ll,ll>,bool>x;
vector<pair<ll,pair<ll,ll>>>edge;

void make_set(ll n)
{
    for(ll i=0; i<n; i++)
    {
        parent[i] = i;
        rankk[i] = 0;
    }
}

int find_set(ll v)
{
    if (v == parent[v])
    {
        return v;
    }
    return parent[v] = find_set(parent[v]);
}

void union_sets(ll a, ll b)
{
    a = find_set(a);
    b = find_set(b);

    if (a != b)
    {
        if(rand()%2)
        {
            swap(a,b);
        }
        parent[b]=a;

        /* else use this
        if (rankk[a] < rankk[b]){swap(a, b);} parent[b] = a; if (rankk[a] == rankk[b]){rankk[a]++;}
        */
    }
}


int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    test
    {
        ll n,m,i,j,k,l=1,c,d,e;

        cin>>n>>m;

        edge.clear();
        x.clear();
        parent.resize(n+2);
        rankk.resize(n+2);
        make_set(n+2);


        for(i=0; i<m; i++)
        {
            cin>>c>>d>>e;

            edge.push_back({e,{c,d}});
        }

        sort(edge.begin(),edge.end());

        l=0;
        k=INT_MAX;

        ///1st MST
        for(auto dd:edge)
        {
            if(find_set(dd.second.second)!=find_set(dd.second.first))
            {
                x[ {dd.second.first,dd.second.second}]=1;
                l+=dd.first;
                union_sets(dd.second.first,dd.second.second);
            }
        }


        ///2nd best MST
        for(auto dd:edge)
        {
            if(x[ {dd.second.first,dd.second.second}]==1)
            {
                d=0;
                e=1;

                make_set(n+2);

                for(auto ee:edge)
                {
                    if(find_set(ee.second.second)!=find_set(ee.second.first) && dd!=ee)
                    {
                        d+=ee.first;
                        e++;
                        union_sets(ee.second.first,ee.second.second);
                    }

                    if(e>=n)
                    {
                        k=min(k,d);
                        break;
                    }
                }
            }
        }

        cout<<l<<" "<<k<<endl;
    }

    return 0;
}


/*

for(i=0; i<m; i++)
{
    if(x[ {edge[i].second.first,edge[i].second.second}]==1)
    {
        e=1;
        d=0;

        make_set(n+2);

        for(j=0; j<m; j++)
        {
            if(find_set(edge[j].second.second)!=find_set(edge[j].second.first) && i!=j)
            {
                d+=edge[j].first;
                e++;
                union_sets(edge[j].second.first,edge[j].second.second);
            }

            if(e>=n)
            {
                k=min(k,d);
                break;
            }
        }
    }
}


*/