合作网络（Corporative Network ）并查集+路径压缩

 #include <iostream>
 #include <algorithm>
 #include <string>
 using namespace std;

 const int maxn =  + ;
 int fa[maxn];
 int d[maxn];

 int Find(int x){
     if (fa[x] != x){
         int root = Find(fa[x]);
         d[x] += d[fa[x]];    //路径压缩维护d[i]
         return fa[x] = root;
     }
     else
         return x;
 }

 int main(){
     /*
     freopen("in.txt", "r", stdin);
     freopen("out.txt", "w", stdout);
     */
     int t;
     cin >> t;
     while (t--){
         int n;
         cin >> n;

         //init
         for (int i = ; i <= n; i++){
             fa[i] = i;
             d[i] = ;
         }

         string s;
         while (cin >> s){
             if (s[] == 'O')
                 break;
             if (s[] == 'I'){
                 int a, b;
                 cin >> a >> b;
                 fa[a] = b;
                 d[a] = abs(a - b) % ;
             }
             else{
                 int c;
                 cin >> c;
                 Find(c);
                 cout << d[c] << endl;
             }
         }
     }
     /*
     fclose(stdin);
     fclose(stdout);
     */
     return ;
 }