Krushkal Implementation

#include <bits/stdc++.h>

using namespace std;

int g_nodes, g_edges, f, t, w;
vector<int> parent(3001, -1);

int root(int x){
    if(x == parent[x])
    return x;
return root(parent[x]);
}

void unio(int x, int y){
    int p = root(x);
    int q = root(y);
    parent[p] = parent[q];
}

void kruskals(pair<int, pair<int, int> > g[]) {
    int cost = 0;
    sort(g, g+g_edges);
    for(int i=1; i<=g_nodes; ++i)
        parent[i] = i;
    for(int i=0; i<g_edges; ++i){
        int x = g[i].second.first;
        int y = g[i].second.second;
        if(root(x) != root(y)){
            unio(x, y);
            cost += g[i].first;
        }
    }
    cout<<cost<<endl;
}

int main()
{
    ios_base::sync_with_stdio(false);
    cin>>g_nodes>>g_edges;
    pair<int, pair<int, int> > g[g_edges];
    for (int i = 0; i < g_edges; i++) {
        cin>>f>>t>>w;
        g[i] = make_pair(w, make_pair(f, t));
    }
    kruskals(g);
    return 0;
}