[NOI2002]银河英雄传说

 1 #include<iostream>
 2 #include<algorithm>
 3 const int N=30001;
 4 class UnionFindSet {
 5     private:
 6         int anc[N],w[N],end[N];
 7         int Find(int x) {
 8             if(x==anc[x]) return x;
 9             int t=Find(anc[x]);
10             w[x]+=w[anc[x]];
11             return anc[x]=t;
12         }
13     public:
14         UnionFindSet() {
15             for(int i=1;i<N;i++) {
16                 anc[i]=end[i]=i;
17                 w[i]=0;
18             }
19         }
20         void Union(int x,int y) {
21             int t=Find(x);
22             w[t]=1;
23             anc[t]=end[Find(y)];
24             end[Find(y)]=end[t];
25         }
26         int Query(int x,int y) {
27             return (Find(x)==Find(y))?std::abs(w[x]-w[y])-1:-1;
28         }
29 };
30 UnionFindSet set;
31 int main() {
32     std::ios_base::sync_with_stdio(false);
33     int t;
34     std::cin>>t;
35     while(t--) {
36         char op;
37         int x,y;
38         std::cin>>op>>x>>y;
39         if(op==‘M‘) {
40             set.Union(x,y);
41         }
42         else {
43             std::cout<<set.Query(x,y)<<std::endl;
44         }
45     }
46     return 0;
47 }