პრიმის ალგორითმი

// Green ))
#include<iostream>
#include<stdio.h>
#include<cstdlib>
#include<math.h>
#include<algorithm>
#include<fstream>
#include<string>
#include<queue>
#include<bitset>
#include<stack>
#include <cstdio>
#include <iomanip>
#include <cstdlib>
#include <cmath>
#include <vector>
#include <set>
#include <map>
#include <deque>
#include <list>
#include <cstring>
#include <cassert>
#include <ctime>
#include <complex>
#define PI 3.141592653589793
#define INF 100000000
#define UNSIGNED 4294967295 //INF
using namespace std;
int a[101][101]={0},s,maxc,n,m,h,v;
vector <int> g,viz;
int main(){
 freopen("input.txt","r",stdin);
 freopen("output.txt","w",stdout);
  cin>>n>>m;
  viz.resize(n+1,0);
 for (int i=1;i<=m;i++){
     int x,y,c;
      cin>>x>>y>>c;
      a[x][y]=a[y][x]=c;
      }
      v=1;
        while (g.size()<n){
     g.push_back(v);
     viz[v]=1;
     maxc=INF;
     for (int i=0;i<g.size();i++)
         for (int j=1;j<=n;j++)
             if (a[g[i]][j]>0 && viz[j]==0)
                  if (a[g[i]][j]<maxc){
                                    maxc=a[g[i]][j];
                                    v=j;
                                    }
                  if (maxc==INF) maxc=0;
                  s+=maxc;
}
      cout<<s;
return 0;
}