双色，三色河内塔（Hanoi2Colors）

问题说明：

       双色，三色河内塔是由河内塔演变而来的一种算法。

public class Hanoi2Colors { 
    public static void help() {
        System.out.println(
              "Usage: java Hanoi2Colors number_of_disks");
        System.out.println(
              "\t number_of_disks: must be a even number.");
        System.exit(0);
    }
    
    public static void main(String[] args) {
        int disks = 0;        
        try {
            disks = Integer.parseInt(args[0]);
        } catch (Exception e) {
            help();
        }
        if ((disks <= 0) || (disks % 2 != 0)) { 
            help(); 
        }
        hanoi2colors(disks);
    }
     
    public static void hanoi(int disks, 
                      char source, char temp, char target) {
        if (disks == 1) {
            System.out.println("move disk from " 
                               + source + " to " + target);
            System.out.println("move disk from " 
                               + source + " to " + target);
        } else {        
            hanoi(disks-1, source, target, temp);
            hanoi(1, source, temp, target);
            hanoi(disks-1, temp, source, target);
        }
    }

    public static void hanoi2colors(int disks) {
        char source = 'A';
        char temp = 'B';
        char target = 'C';
        for (int i = disks / 2; i > 1; i--) {
            hanoi(i-1, source, temp, target);
            System.out.println("move disk from " 
                                   + source + " to " + temp);
            System.out.println("move disk from " 
                                   + source + " to " + temp); 
            hanoi(i-1, target, temp, source);
            System.out.println("move disk from " 
                                   + temp + " to " + target);
        }
        System.out.println("move disk from " 
                                   + source + " to " + temp);
        System.out.println("move disk from " 
                                 + source + " to " + target);
    }
} 

三色河内塔

public class Hanoi3Colors {    
    public static void help() {
        System.out.println(
              "Usage: java Hanoi3Colors number_of_disks");
        System.out.println(
      "\tnumber_of_disks: must be a number divisible by 3.");
        System.exit(0);
    }
    
    public static void main(String[] args) {
        int disks = 0;        
        try {
            disks = Integer.parseInt(args[0]);
        } catch (Exception e) {
            help();
        }
        if ((disks <= 0) || (disks % 3 != 0)) { 
            help(); 
        }
        hanoi3colors(disks);
    }
    
    public static void hanoi(int disks, 
                       char source, char temp, char target) {
        if (disks == 1) {
            System.out.println("move disk from " 
                               + source + " to " + target);
            System.out.println("move disk from "
                               + source + " to " + target);
            System.out.println("move disk from "
                               + source + " to " + target);
        } else {        
            hanoi(disks-1, source, target, temp);
            hanoi(1, source, temp, target);
            hanoi(disks-1, temp, source, target);
        }
    }
    
    public static void hanoi3colors(int disks) {
        char source = 'A';
        char temp   = 'B';
        char target = 'C';
        if (disks == 3) {
            System.out.println("move disk from " 
                            + source + " to " + temp);
            System.out.println("move disk from " 
                            + source + " to " + temp);
            System.out.println("move disk from " 
                            + source + " to " + target);
            System.out.println("move disk from " 
                            + temp + " to " + target);
            System.out.println("move disk from " 
                            + temp + " to " + source);
            System.out.println("move disk from " 
                            + target + " to " + temp);
        } else {
            hanoi(disks/3-1, source, temp, target);
            System.out.println("move disk from " 
                            + source + " to " + temp);
            System.out.println("move disk from " 
                            + source + " to " + temp);
            System.out.println("move disk from " 
                            + source + " to " + temp);
            hanoi(disks/3-1, target, temp, source);
            System.out.println("move disk from " 
                            + temp + " to " + target);
            System.out.println("move disk from "
                            + temp + " to " + target);
            System.out.println("move disk from "
                            + temp + " to " + target);
            hanoi(disks/3-1, source, target, temp);
            System.out.println("move disk from " 
                            + target + " to " + source);
            System.out.println("move disk from " 
                            + target + " to " + source);
            hanoi(disks/3-1, temp, source, target);
            System.out.println("move disk from " 
                            + source + " to " + temp);
        
            for (int i = disks / 3 - 1; i > 0; i--) {
                if (i>1) { 
                    hanoi(i-1, target, source, temp); 
                }
                System.out.println("move disk from " 
                         + target + " to " + source);
                System.out.println("move disk from " 
                         + target + " to " + source);
                if (i>1) { 
                    hanoi(i-1, temp, source, target); 
                }
                System.out.println("move disk from " 
                         + source + " to " + temp);
            }
        }
    }
}

评论

1 楼 namelessmyth 2009-06-27  

我来顶你啦,哈哈.