?????? 該程序用一個數組id，其中每項對應一個對象，讀取小于N個非負整數對序列（‘p q’，意思為對象p與對象q連通），并且打印在給出的連通對基礎上還沒有連通的對。定義如下屬性：當且僅當p與q連通時，id[p]=id[q]。

?????? 例如輸入3 4，由于先前沒有任何連通對，所以打印3 4，再輸入 4 9 ，先前給出的連通對是3 4，在此基礎上得不到4 9連通（即把4 9識為提供了一個新的連通），所以同樣打印4 9，當再輸入3 9的時候，由于前面已經給出了3 4及4 9，由可傳遞性可以得到3 9連通，即3 9不再是一個新的連通，故不打印。
?
public class QuickF
? {
??? public static void main(String[] args)
??? {
????? int N = Integer.parseInt(args[0]);
????? int id[] = new int[N];
????? for (int i = 0; i < N ; i++) id[i] = i;
????? for( In.init(); !In.empty(); )
??????? {
????????? int p = In.getInt(), q = In.getInt();
????????? int t = id[p];
????????? if (t == id[q]) continue;
????????? for (int i = 0;i<N;i++)
??????????? if (id[i] == t) id[i] = id[q];
????????? Out.println(p+" "+q+" ");
??????? }
??? }
? }??
?
? public class Out
? {
??? public static void print(String s)
???? {
?System.out.print(s);
???? }
??? public static void println(String s)
???? {
??????? System.out.println(s);
???? }
? }

? import java.io.*;
? public class In
? {
??? private static int c;

??? private static boolean blank()
????? {
??????? return Character.isWhitespace((char) c);
????? }
??? private static void readC()
????? {
??????? try
????????? {
??????????? c = System.in.read();
????????? }
??????? catch (IOException e)
????????? {
??????????? c = -1;
????????? }
????? }
??? public static void init()
????? {
??????? readC();
????? }
??? public static boolean empty()
????? {
??????? return c == -1;
????? }
??? public static String getString()
????? {
??????? if (empty()) return null;
??????? String s = "";
??????? do
????????? {
??????????? s += (char) c; readC();
????????? }
??????? while (!(empty() | blank()));
??????? while (!empty() && blank()) readC();
??????? return s;
????? }
??? public static int getInt()
????? {
??????? return Integer.parseInt(getString());
????? }
??? public static double getDouble()
????? {
??????? return Double.parseDouble(getString());
????? }
?? }

?