Pour oil problem, breadth optimization search, Java

There is a chef from 12 pounds of oil (a barrel) of the barrels poured out 6 kilograms of oil, but only 8 pounds of oil (b barrels) and 5 pounds of oil (c barrels) Two barrels, asked how to operate to be 6 pounds out of it?
Class Dumpoilbfs:

Import Cn.hncu.sreach.putoil.common.bucket;import Cn.hncu.sreach.putoil.common.dumpcase;import cn.hncu.sreach.putoil.common.myset;/* a chef to from 12 pounds of oil (a barrel) of the barrels poured out 6 kilograms of oil, but only 8 pounds of oil (b barrels) and 5 pounds of oil (c barrels) Two barrels, asked how to operate to be 6 pounds out of it? * The breadth of the problem to optimize the search solution: every oil, there may be 6 kinds of programs, each one to judge if there is no 6 catty situation, if it appears on the record, and then continue to search, until all the circumstances of the search finished. * Detailed comments are below. */public class Dumpoilbfs {public static void main (string[] args) {bucket[] buckets = new bucket[3];//new array length is 3, representing 3 barrels Buc Kets[0] = new Bucket (12, 12); The first bucket of properties, the size of the bucket of 12 pounds, the existing 12 Jin buckets[1] = new Bucket (8, 0); The first bucket of properties, the size of the bucket of 8 pounds, the existing 0 Jin buckets[2] = new Bucket (5, 0); The first bucket of properties, the size of the bucket is 5 pounds, the existing 0 Jin dumpcase u = new dumpcase (buckets); New duampcase, used to represent the state of three buckets now myset caseset = new MySet (); New MySet, used to indicate the state of the three buckets that have occurred, followed by steps to prevent repetition caseset.add (u); Casequeue que = new casequeue (); A queue that is used to load the state of the current three barrels and the state of the caseset at this time que.enqueue (U, Caseset); BFs (que); Go to breadth optimization search}//breadth optimization search private static void BFs (Casequeue que) {while (!que.isempty ()) {///If the queue is empty, exit q q = Que.dequeque () directly; Remove an element from a queue qdumpcase u = qUe.getdumpcase (q); Extracting Dumpcasemyset Caseset = Que.getmyset (q) from Q; Extract the dumpcase//from Q to determine if there is a bucket of oil for 6 Jin, exit the loop if (U.buckets[0].now = = 6 | | u.buckets[1].now = = 6) {print (U, caseset);//Output path C Ontinue; There is no break here, otherwise it will only come out a situation//break;}  Dumpcase temp = new Dumpcase (u);//backup here once so that later restore//here is the core for (int i = 0; i < temp.buckets.length; i++) {for (int j = 0; J < Temp.buckets.length; J + +) {if (i = = j) {//cannot pour continue himself and herself;} int incandump = Temp.buckets[i].canout ();  See how much this can be poured if (Incandump > Temp.buckets[j].canin ()) {//To determine whether the amount of the can pour is greater than the amount received Incandump = Temp.buckets[j].canin (); If it is greater than that, then you can pour out all I}if (incandump = = 0) {//If you pour in continue;} Begin to pour the oil, reduce the reduction, the addition of Temp.buckets[i].out (Incandump), temp.buckets[j].in (Incandump),//To determine whether or not before the end of the case if ( Caseset.contains (temp)) {//If present, restore temp.buckets[i].in (incandump); Temp.buckets[j].out (incandump); continue;}  Dumpcase v = new Dumpcase (temp); v.parent = u; Record the parent node Caseset.add (v);//record to the set of nodes that have been searched Que.enqueue (V, caseset);//Add to the wide search queue//must be restored in order to continue to try other paths from this node temp.buckets[I].in (Incandump); Temp.buckets[j].out (Incandump);}}} Output path (output in reverse order), the next need to output is the previous parent node private static void Print (Dumpcase u, myset caseset) {MySet set = new MySet (); Set.add (U);D Umpcase d = u.parent;while (d! = null) {Set.add (d);d = D.parent;} object[] obj = Set.getall (); for (int i = obj.length-1; I >= 0; i--) {if (i > 0) {System.out.print (Obj[i] + "---&G T;> ");} else {System.out.println (obj[i]);}}} Object for loading dumpcase and MySet class Q {public dumpcase d;public MySet m;//Constructor public Q (Dumpcase D, MySet m) {this.d = D;THIS.M = n EW MySet (m);} Public Dumpcase getd () {return D;} Public MySet Getm () {return m;}} Queue (elements in the queue are objects bundled with Dumpcase and MySet) class Casequeue {private q[] qs = new q[100];D umpcase u = null; MySet set = Null;int end = 0; A queue pointer representing the number of elements in the queue//into the queue public int enqueue (dumpcase u, myset caseset) {qs[end++] = new Q (u, caseset); return end;} Public Dumpcase getdumpcase (q q) {return q.d;} Public MySet Getmyset (q q) {return q.m;} Out Queue public Q Dequeque () {if (IsEmpty ()) {return null;} Q q = qs[0]; Each time is the first element of the popup queue//All elements move forward one if (end > 1) {for (int i = 0; i < end; i++) {Qs[i] = qs[i + 1];}} End--;return Q;} Determines whether null public boolean isEmpty () {if (end = = 0) {return true;} return false;}}

Class Buckets:

public class Buckets {public int max;//represents the maximum capacity of a bucket public int now;//= number of oil in the current bucket//constructor public bucket (int max, int. now) {This.ma x = Max;this.now = Now;} The current maximum number of oil public int canIn () {return max-now;} Indicates the current maximum amount of oil that can be poured public int canout () {return now;} Indicates how much oil was added public void in (int a) {now + = A;} Indicates poured out, how much oil public void out (int. a) {now-= A;} @Overridepublic int hashcode () {final int prime = 31;int result = 1;result = Prime * result + Max;result = Prime * result + Now;return result;} @Overridepublic boolean equals (Object obj) {if (this = = obj) return true;if (obj = = null) return False;if (GetClass ()! = obj . GetClass ()) return false; Bucket other = (bucket) obj;if (max! = Other.max) return false;if (now! = Other.now) return False;return true;}}

Class Dumpcase:

Import Java.util.arrays;public class Dumpcase {public Bucket buckets[] =null;public dumpcase parent=null;public DumpCase (Bucket buckets[]) {this.buckets = buckets;} Copy construction (here to be very careful to prevent bundling) public dumpcase (Dumpcase u) {buckets = new bucket[u.buckets.length];//Copy the elements of U into the new buckets for (int i=0;i<u.buckets.length;i++) {Buckets[i] = new Bucket (0,0); Buckets[i].max = U.buckets[i].max;buckets[i].now = U.buckets[i].now;}} @Overridepublic String toString () {return "a=" +buckets[0].now+ "b=" +buckets[1].now+ "c=" +buckets[2].now;} @Overridepublic int hashcode () {final int prime = 31;int result = 1;result = Prime * result + arrays.hashcode (buckets); RET Urn result;} @Overridepublic boolean equals (Object obj) {if (this = = obj) return true;if (obj = = null) return False;if (GetClass ()! = obj . GetClass ()) return false;dumpcase other = (dumpcase) obj;if (! Arrays.equals (buckets, other.buckets)) return False;return true;}}

Class MySet:

public class MySet {private object[] Objs = new object[0];//copy construction (prevents bundling) This is not the first time to write, because after debugging found that the total number of paths can not be,// This is to make a copy of the current state of Caseset each time it joins the queue, but there is still no output of all the values public MySet (MySet m) {objs = new Object[m.getall (). length];for (int i = 0; i < objs.length; i++) {Objs[i] = new Object (); Objs[i] = M.getall () [i];}} Public MySet () {}//Add function public boolean add (Object obj) {if (contains (obj)) {//If there are duplicates, do not put in return false;} Object tempobjs[] = new Object[objs.length + 1];//with dynamic array system.arraycopy (OBJS, 0, TEMPOBJS, 0, objs.length); tempobjs[obj S.length] = Obj;objs = Tempobjs;return true;} Determines whether there is a duplicate element public boolean contains (object obj) {for (object O:objs) {if (o.equals (obj)) {return true;}} return false;} Gets all the elements in MySet public object[] GetAll () {return OBJS;} Gets the number of elements of the MySet public int size () {return objs.length;}}

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Pour oil problem, breadth optimization search, Java