合作网络（Corporative Network ）并查集+路径压缩

 1 #include <iostream>
 2 #include <algorithm>
 3 #include <string>
 4 using namespace std;
 5 
 6 const int maxn = 20000 + 5;
 7 int fa[maxn];
 8 int d[maxn];
 9 
10 int Find(int x){
11     if (fa[x] != x){
12         int root = Find(fa[x]);
13         d[x] += d[fa[x]];    //路径压缩维护d[i]
14         return fa[x] = root;
15     }
16     else
17         return x;
18 }
19 
20 int main(){
21     /*
22     freopen("in.txt", "r", stdin);
23     freopen("out.txt", "w", stdout);
24     */
25     int t;
26     cin >> t;
27     while (t--){
28         int n;
29         cin >> n;
30         
31         //init
32         for (int i = 1; i <= n; i++){
33             fa[i] = i;
34             d[i] = 0;
35         }
36 
37         string s;
38         while (cin >> s){
39             if (s[0] == ‘O‘)
40                 break;
41             if (s[0] == ‘I‘){
42                 int a, b;
43                 cin >> a >> b;
44                 fa[a] = b;
45                 d[a] = abs(a - b) % 1000;
46             }
47             else{
48                 int c;
49                 cin >> c;
50                 Find(c);
51                 cout << d[c] << endl;
52             }
53         }
54     }
55     /*
56     fclose(stdin);
57     fclose(stdout);
58     */
59     return 0;
60 }