Java简单实现农夫过河问题示例

2019-11-26 10:44:43

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本文实例讲述了Java简单实现农夫过河问题。分享给大家供大家参考，具体如下：

一、问题描述

老伯伯要带鱼、狗、猫过河到对岸.，有一条船，只能坐一个人，老伯每次只能带一样动物过河，当老伯不在的时侯狗会咬猫，猫会吃鱼.，请问怎么顺序过河呢？

二、实现代码

package demo;import java.util.ArrayList;import java.util.List;public class CrossRiver {    List<String> listThis = new ArrayList<String>();    List<String> listThat = new ArrayList<String>();    /*boolean thisFlag = true;    boolean thatFlag = false;*/    public CrossRiver() {        listThis.add("dog");        listThis.add("fish");        listThis.add("cat");        // listThis.add("people");    }    public boolean isSafe(@SuppressWarnings("rawtypes") List list){        if(list.contains("fish")&&list.contains("cat")||list.contains("cat")&&list.contains("dog")){            return false;        }else{            return true;        }    }    public void thisTothat(){        String str = listThis.get(0);        listThis.remove(str);        if(this.isSafe(listThis)){            System.out.println("农夫带着 " + str + " 从此岸到彼岸");            System.out.println("此岸" + listThis + "/b" + "彼岸" + listThat);            System.out.println();            listThat.add(str);            thatToThis();        }else{            listThis.add(str);            thisTothat();        }    }    public void thatToThis(){        if(listThis.isEmpty()){            System.out.println("此岸" + listThis + "/b" + "彼岸" + listThat);            return;        }        if(isSafe(listThat)){            System.out.println("农夫从彼岸到此岸");            System.out.println("此岸" + listThis + "/b" + "彼岸" + listThat);            System.out.println();            thisTothat();        }else{            String str = listThat.get(0);            listThat.remove(0);            if(isSafe(listThat)){                System.out.println("农夫带着 " + str + " 从彼岸到此岸");                System.out.println("此岸" + listThis + "/b" + "彼岸" + listThat);                System.out.println();                listThis.add(str);                thisTothat();            }else{                listThat.add(str);                thatToThis();            }        }    }    public static void main(String[] args){        System.out.println("武林网测试结果：");        System.out.println();        new CrossRiver().thisTothat();    }}

运行结果：