4. 5G网络建设

const readline = require('readline');
const rl = readline.createInterface({
    input: process.stdin,
    output: process.stdout,
});

const lines = [];
rl.on('line', (line) => {
    lines.push(line);
});
rl.on('close', () => {
    class Edge {
        constructor(u, v, cost, pre) {
            this.u=u;
            this.v=v;
            this.cost = cost;
            this.pre = pre;
        }
    }

    function union(x, y) {
        let rootX = find(X);
        let rootY = find(Y);
        if (rootX != rootY) {
            parent[rootX] = rootY;
        }
    }
    function find(x) {
        if (parent[x] !== x) {
            parent[x] = find(parent[x]);// 路径压缩
        }
        return parent[x];
    }
    let N = parseInt(lines[0]);
    let M = parseInt(lines[1]);
    let parent = Array.from({length: N+1}, (_, i) => i);
    let edges = []; //存储所有边

    for(let i=2; i<lines.length; i++) {
        let [X,Y,Z,P] = lines[i].split(' ').map(Number);
        edges.push(new Edge(X,Y,Z,P));
        if(P === 1) {
            union(X, Y);
        }
    }

    edges.sort((a, b) => a.cost - b.cost);
    let cost = 0;
    for(let edge of edges) {
        if (find(edge.u) !== find(edge.v)) {
            cost += edge.cost;
            union(edge.u, edge.v);
        }
    }
    for(let i=2; i<=N; i++) {
        if (find(i) !== find(1)) {
            console.log(-1);
            return;
        }
    }
    console.log(cost);
})