PPP DSU

#include <bits/stdc++.h>
using namespace std;
vector<int>parent;
struct edge{
    int from, to, weight;
    edge(int u,int v, int w): from(u),to(v),weight(w){}

    bool operator < (const edge& p) const {
        return weight < p.weight;
    }

};

vector<edge>graph;

int findParent(int node)
{
    if(parent[node] == node)
        return node;
    return parent[node] = findParent(parent[node]);
//    return parent[node]==node ? node : parent[node] = findParent(parent[node]);
}

int mst(int nodeNumber)
{
    sort(graph.begin(),graph.end());

    for(int i = 1 ;i <= nodeNumber; i++)
        parent[i] = i;
    int cost = 0;
    for(int i = 0 ; i < graph.size(); i++)
    {
        int from = findParent(graph[i].from);
        int to = findParent(graph[i].to);

        if(from!=to)
        {
            parent[to] = from;
            cost += graph[i].weight;
        }
    }
    return cost;
}

int main()
{
    int nodeCount, edgeCount;
    cin >> nodeCount >> edgeCount;
    parent.resize(nodeCount+1);

    for(int i = 1 ; i <= edgeCount; i++)
    {
        int u,v,w;
        cin >> u >> v >> w;
        graph.push_back(edge(u,v,w));
    }

    cout<<mst(nodeCount)<<endl;

    return 0;
}