27   EC.reserve(N);  in grow()
28   while (EC.size() < N)  in grow()
29     EC.push_back(EC.size());  in grow()
34   unsigned eca = EC[a];  in join()
35   unsigned ecb = EC[b];  in join()
41       EC[b] = eca, b = ecb, ecb = EC[b];  in join()
43       EC[a] = ecb, a = eca, eca = EC[a];  in join()
48   while (a != EC[a])  in findLeader()
49     a = EC[a];  in findLeader()
56   for (unsigned i = 0, e = EC.size(); i != e; ++i)  in compress()
57     EC[i] = (EC[i] == i) ? NumClasses++ : EC[EC[i]];  in compress()
64   for (unsigned i = 0, e = EC.size(); i != e; ++i)  in uncompress()
65     if (EC[i] < Leader.size())  in uncompress()
66       EC[i] = Leader[EC[i]];  in uncompress()
68       Leader.push_back(EC[i] = i);  in uncompress()