Given n nodes labeled from 0 to n - 1 and a list of undirected edges (each edge is a pair of nodes), write a function to find the number of connected components in an undirected graph.Example 1:     0          3     |          |     1 --- 2    4Given n = 5 and edges = [[0, 1], [1, 2], [3, 4]], return 2.Example 2:     0           4     |           |     1 --- 2 --- 3Given n = 5 and edges = [[0, 1], [1, 2], [2, 3], [3, 4]], return 1.Note:You can assume that no duplicate edges will appear in edges. Since all edges are undirected, [0, 1] is the same as [1, 0] and thus will not appear together in edges.

Use Union Find to figure out the number of connected components

1 public class Solution { 2     public int countComponents(int n, int[][] edges) { 3         unionFind uf = new unionFind(n); 4         for (int[] edge : edges) { 5             if (!uf.isConnected(edge[0], edge[1])) { 6                 uf.union(edge[0], edge[1]); 7             } 8         } 9         return uf.findCount();10     }11     12     public class unionFind{13             int[] ids;14             int count;15             16             public unionFind(int num) {17                 this.ids = new int[num];18                 for (int i=0; i