ACM Find them, Catch them

 1 /*
 2     Name: Find them, Catch them 
 3     Copyright: 
 4     Author: 
 5     Date: 09/08/17 09:27
 6     Description: 给定两个集合，通过已给信息，判断两个元素是否同一集合。
 7                 如果是，则输出 "In the same gang."
 8                 如果不是，则输出"In different gangs."
 9                 如果不能从已给信息判断，则输出 "Not sure yet."
10 */
11 #include<iostream>
12 #include<algorithm>
13 #include<stdio.h>
14 using namespace std;
15 const int N = 500005;
16 int parent[N],rank[N];
17 
18 void init() /*初始化*/
19 {
20     for(int i = 0; i < N; i++)
21     {
22         parent[i] = i;
23         rank[i] = -1;
24     }
25             
26 } 
27 int find(int n)
28 {
29     if(n !=parent[n])
30         parent[n] = find(parent[n]);
31     return parent[n];
32 }
33 /*
34 使用这个函数竟然给我TLE  =  =、
35 int find(int n)
36 {
37     if(n == parent[n])
38         return n;
39     else
40         return find(parent[n]);
41 }
42 */
43 void merge(int a,int b)
44 {
45      a = find(a);
46      b = find(b);
47      if(a != b)
48          parent[a] = b;    
49 }
50 int main()
51 {
52     int t,m,n,a,b;
53     char ch;
54     while(cin>>t)
55     {
56         while(t--)
57         {
58             int temp = 0;
59             init();
60             scanf("%d %d",&n,&m);
61             for(int i = 0; i < m; i++)
62             {
63                 getchar();
64                 scanf("%c %d %d",&ch,&a,&b);
65                 //cin>>Node[i].ch>>Node[i].a>>Node[i].b;  在循环次数较多情况下使用scanf 使用cin容易TLE！ 
66                 if(ch == ‘D‘)
67                 {
68                     if(rank[a] != -1)  merge(rank[a],b);
69                     if(rank[b] != -1)  merge(rank[b],a);
70                      rank[a] = b;
71                      rank[b] = a;
72                     
73                 }else{
74                     if( find(a) == find(b))
75                         printf("In the same gang.\n");
76                     else if(find(rank[a]) == find(b))
77                         printf("In different gangs.\n");
78                     else
79                         printf("Not sure yet.\n");
80                 }
81             }
82         }
83     }
84     return 0;
85 }