//广度优先搜索

// 2014-10-24

import java.util.ArrayList;

import java.util.HashSet;

import java.util.LinkedList;

import java.util.List;

import java.util.Queue;

import java.util.Scanner;

import java.util.Set;

public class Water {

int CA = 11; // 两个桶的容量

int CB = 4;

int dest = 3; // 目标

// 6个操作

String opName[] = { "装满A桶 ", "装满B桶 ", "清空A桶 ", "清空B桶 ",

"A中水倒入B", "B中水倒入A", };

// 搜索队列

Queue queue = new LinkedList();

// 结点

class Node {

int qa = 0;

int qb = 0;

@Override

public int hashCode() {

int ret = qa * 1024 + qb;

return ret;

}

@Override

public boolean equals(Object n){

Node nd = (Node)n;

return nd.qa == qa && nd.qb == qb;

}

}

// 带路径的结点

class PathNode extends Node {

List path = new ArrayList();

}

PathNode pnResult;

// 已访问结点

Set visited = new HashSet();

// 根据操作码进行操作

void operate(PathNode nd, int code) {

switch (code) {

case 0:

nd.qa = CA;

break;

case 1:

nd.qb = CB;

break;

case 2:

nd.qa = 0;

break;

case 3:

nd.qb = 0;

break;

case 4:

if (nd.qa <= CB - nd.qb) {

nd.qb += nd.qa;

nd.qa = 0;

} else {

nd.qa -= CB - nd.qb;

nd.qb = CB;

}

break;

case 5:

if (nd.qb <= CA - nd.qa) {

nd.qa += nd.qb;

nd.qb = 0;

} else {

nd.qb -= CA - nd.qa;

nd.qa = CA;

}

break;

}

nd.path.add(code);

}

// 成功

boolean success(Node nd) {

return nd.qa == dest || nd.qb == dest

|| (dest > nd.qa && dest > nd.qb && dest == nd.qa + nd.qb);

}

// 已访问

boolean visited(Node nd) {

return visited.contains(nd);

}

void search() {

PathNode pn = new PathNode();

queue.offer(pn);

visited.add(pn);

int status = 0; // 0搜索，1成功，2失败

while (status == 0) {

if (queue.isEmpty()) {

status = 2;

} else {

PathNode pnOld = queue.poll();

for (int i = 0; i <= 5; i++) {

PathNode pnNew = new PathNode();

pnNew.qa = pnOld.qa;

pnNew.qb = pnOld.qb;

pnNew.path.addAll(pnOld.path);

this.operate(pnNew, i);

if (success(pnNew)) {

status = 1;

pnResult = pnNew;

break;

} else if (!visited(pnNew)) {

visited.add(pnNew);

queue.offer(pnNew);

}

} // end of for

}

} // end of while

if (status == 1) {

print(pnResult);

} else {

System.out.println("无解");

}

}

void print(PathNode pn) {

PathNode pathResult = new PathNode();

for (Integer i : pn.path) {

this.operate(pathResult, i);

System.out.println(opName[i] + "\t\t\t--->" + pathResult.qa + ' '

+ pathResult.qb);

}

}

void input() {

System.out.println("依次输入A B桶的容量和目标水量，如6 5 3");

Scanner sc = new Scanner(System.in);

CA = sc.nextInt();

CB = sc.nextInt();

dest = sc.nextInt();

sc.close();

}

public static void main(String args[]) {

Water w = new Water();

w.input();

w.search();

}

}

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