краскал

#include<iostream>
using namespace std;

const int INF = 10000;

struct rebro
{
 int begin, end, ves;
 void new_rebro(int begin, int end, int ves)
 {
   this->begin = begin;
   this->end = end;
   this->ves = ves;
 }
};

class Graph
{
  private:
  int n, shet_reber, dlina = 0;
  int *color, **path;
  rebro *arr;

  public:
  Graph (rebro *matrix, int x, int shet)
  {
    n = x;
    shet_reber = shet;
    arr = matrix;
    color = new int[n];

    for (int i = 0; i < n; i++)
     color[i] = i;

    path = new int*[n];

    for(int i = 0; i < n; i++)
     path[i] = new int[n];

    for(int i = 0; i < n; i++)
     for (int j = 0; j < n; j++)
      path[i][j] = 0;
  }

  void sort_reber(int first, int last);
  void algorithm_kras();
  void get_result_kras();
};

void Graph::sort_reber(int first, int last)
{
int x, i, j, c = first, d = last;

while (c < d)
{
  int m = (c+d)/2;

 if (arr[c].ves > arr[d].ves && arr[c].ves < arr[m].ves)
 x = arr[c].ves;
  else if (arr[d].ves > arr[c].ves && arr[d].ves < arr[m].ves)
   x = arr[d].ves;
    else x = arr[m].ves;

 i = c;
 j = d;

   while (i < j)
   {
    while (arr[i].ves < x)
     i++;
    while (arr[j].ves > x)
     j--;

    if (i <= j)
     {
       swap(arr[i], arr[j]);
       i++;
       j--;
     }
   }

if (j-c < d-i)
 {
   if (c < j)
    sort_reber(c, j);
    c = i;
 }
else
 {
   if (i<d)
  sort_reber(i, d);
   d = j;
 }
}
}

void Graph::algorithm_kras()
{
 for(int i = 0; i < shet_reber; i++)
  {
    if (color[arr[i].begin] != color[arr[i].end])
     {
       path[arr[i].begin][arr[i].end] = arr[i].ves;
       path[arr[i].end][arr[i].begin] = arr[i].ves;
       dlina += arr[i].ves;

    int old_color = color[arr[i].begin], new_color = color[arr[i].end];
     for (int j = 0; j < n; j++)
      if (color[j] == old_color)
        color[j] = new_color;
     }
  }
}

void Graph::get_result_kras()
{
  cout << dlina << endl;

  for (int i = 0; i < n; i++)
   {
     for(int j = 0; j < n; j++)
      {
        cout.width(3);
        cout << path[i][j] << " ";
      }
      cout << endl;
   }
}

int main()
{
 int n, shet_reber, a, b, w;
 cin >> n >> shet_reber;

rebro *arr = new rebro[shet_reber];

for (int i = 0; i < shet_reber; i++)
  {
    cin >> a >> b >> w;
    a--;
    b--;
    arr[i].new_rebro(a, b, w);
  }

 Graph object(arr, n, shet_reber);
 object.sort_reber(0, shet_reber-1);
 object.algorithm_kras();
 object.get_result_kras();
}