Cod sursă (job #804478)

#include <bits/stdc++.h>
using namespace std;

ifstream fin("zapada.in");
ofstream fout("zapada.out");
set<unsigned short> s;
set<unsigned short> :: iterator it;
vector< pair<short, short> > v[100005];
vector< pair<short, short> > :: iterator it2;
short n, k, t[10002];
int m, costTotal;

void Union(short x, short y)
{
    t[y] = x;
}
short Find(short x)
{
    short y, rad = x;
    while (t[rad] != 0)
        rad = t[rad];
    while (x != rad)
    {
        y = t[x];
        t[x] = rad;
        x = y;
    }
    return rad;
}

void Citire()
{
    int c;
    short x, y;
    fin >> n >> m >> k;
    for (int i = 1; i <= m; i++)
    {
        fin >> x >> y >> c;
        s.insert(c);
        v[c].push_back({x, y});
    }
}
void Afis()
{
    fout << costTotal << "\n";
}
void Kruskal()
{
    short nrc = n, x, y;
    int cost;
    pair<short, short> a;
    for(it = s.begin();it != s.end() && nrc > 1;it++)
    {
        cost = *it;
        for(it2 = v[cost].begin();it2 != v[cost].end() && nrc > 1;it2++)
        {
            a = *it2;
            x = a.first;
            y = a.second;
            x = Find(x);
            y = Find(y);
            if (x != y)
            {
                Union(x, y);
                nrc--;
                costTotal += cost;
            }
        }
    }
    Afis();
}

int main()
{
    int c;
    short x, y;
    Citire();
    Kruskal();
    for(short i = 1;i <= k;i++)
    {
        fin >> x >> y >> c;
        s.insert(c);
        v[c].push_back({x, y});
        costTotal = 0;
        for(short j = 1;j <= n;j++)
            t[j] = 0;
        Kruskal();
    }
    fout.close();
    return 0;
}