leetcode 1319. 连通网络的操作次数

c++

class Solution {
public:
    class UnionSet {
    public:
        int *father, n;
        UnionSet(int n) : n(n) {
            father = new int[n + 1]; 
            for (int i = 0; i <= n; i++) {
                father[i] = i;
            }
        }
        int find(int x) {
            return father[x] = (father[x] == x ? x : find(father[x]));
        }
        void merge(int a, int b) {
            father[find(a)] = find(b);
            return ;
        }
    };
    int makeConnected(int n, vector<vector<int>>& connections) {
        UnionSet u(n);
        int outMac = 0, line = 0;
        for (auto connection : connections) {
            if (u.find(connection[0]) == u.find(connection[1])) line++;
            else u.merge(connection[0], connection[1]);
        }
        for (int i = 0; i < n; i++) {
            if (u.find(i) == i) outMac++; 
        }
        if (line >= outMac - 1) return outMac - 1;
        return -1;
    }
};

js

class UnionSet {
    constructor(n) {
        this.father = new Array(n);
        for (var i = 0; i < n; i++) this.father[i] = i;
    }
    find(x) {
        return this.father[x] = (this.father[x] == x ? x : this.find(this.father[x]));
    }
    merge(a, b) {
        this.father[this.find(a)] = this.find(b); 
    } 
};
var makeConnected = function(n, connections) {
    var u = new UnionSet(n), Mac = 0, line = 0;
    for (var connection of connections) {
        if (u.find(connection[0]) == u.find(connection[1])) line++;
        else u.merge(connection[0], connection[1]);
    }
    for (var i = 0; i < n; i++) {
        if (u.find(i) == i) Mac++;
    }
    if (line >= Mac - 1) return Mac - 1;
    return -1;
};