程序解：现有3L容器和5L容器各一个，问如何量出4L水（水无限）

89 阅读 0 评论 59 点赞

我是靠谱客的博主奋斗大船，这篇文章主要介绍程序解：现有3L容器和5L容器各一个，问如何量出4L水（水无限），现在分享给大家，希望可以做个参考。

穷举所有的可能性，从杯子里面水变化角度来讲，每个状态到下一个状态只有6种行为：3L杯子装满，5L杯子装满，3L倒空，5L倒空，3L倒到5L，5L倒到3L。最终结果如果5L的里面有4L水则得到一个解。如果当前状态和前面一个状态重复，则取消继续往后的探索。

复制代码

public class test{
private static Status[] steps = new Status[100];
public static void main(String[] args){
steps[0] = new Status();
solve(1);
}
private static void solve(final int depth){
//paint(depth-1);
if(duplicate(depth - 1)){
return;
}
if(steps[depth - 1].cup5 == 4){
paint(depth - 1);
return;
}
Status preStatus = steps[depth - 1];
steps[depth] = preStatus.full3();
solve(depth + 1);
steps[depth] = preStatus.full5();
solve(depth + 1);
steps[depth] = preStatus.trans3to5();
solve(depth + 1);
steps[depth] = preStatus.trans5to3();
solve(depth + 1);
steps[depth] = preStatus.empty3();
solve(depth + 1);
steps[depth] = preStatus.empty5();
solve(depth + 1);
}
private static boolean duplicate(int depth){
for(int i=0 ; i < depth ; i++){
if( steps[i].equals(steps[depth])){
return true;
}
}
return false;
}
private static void paint(int depth){
for(int i = 0; i <= depth; i++){
System.out.print(steps[i]+" ");
}
System.out.println();
}
}
class Status{
int cup3;
int cup5;
public Status(){
}
public Status(Status s){
this.cup3 = s.cup3;
this.cup5 = s.cup5;
}
public Status full3(){
Status newStatus = new Status(this);
newStatus.cup3 = 3;
return newStatus;
}
public Status full5(){
Status newStatus = new Status(this);
newStatus.cup5 = 5;
return newStatus;
}
public Status trans3to5(){
Status newStatus = new Status(this);
if(5 - newStatus.cup5 >= newStatus.cup3){
newStatus.cup5 += newStatus.cup3;
newStatus.cup3 = 0;
}else{
newStatus.cup3 -= (5 - newStatus.cup5);
newStatus.cup5 = 5;
}
return newStatus;
}
public Status trans5to3(){
Status newStatus = new Status(this);
if(newStatus.cup5 <= 3 - newStatus.cup3){
newStatus.cup3 += newStatus.cup5;
newStatus.cup5 = 0;
}else{
newStatus.cup5 -= (3 - newStatus.cup3);
newStatus.cup3 = 3;
}
return newStatus;
}
public Status empty3(){
Status newStatus = new Status(this);
newStatus.cup3 = 0;
return newStatus;
}
public Status empty5(){
Status newStatus = new Status(this);
newStatus.cup5 = 0;
return newStatus;
}
public String toString(){
return "["+this.cup3+"#"+this.cup5+"]";
}
public boolean equals(Object o){
if(o == null){
return false;
}
if(o == this){
return true;
}
if(o instanceof Status){
Status s = (Status)o;
return s.cup3 == this.cup3 && s.cup5 == this.cup5;
}
return false;
}
}

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
public class test{
private static Status[] steps = new Status[100];
public static void main(String[] args){
steps[0] = new Status();
solve(1);
}
private static void solve(final int depth){
//paint(depth-1);
if(duplicate(depth - 1)){
return;
}
if(steps[depth - 1].cup5 == 4){
paint(depth - 1);
return;
}
Status preStatus = steps[depth - 1];
steps[depth] = preStatus.full3();
solve(depth + 1);
steps[depth] = preStatus.full5();
solve(depth + 1);
steps[depth] = preStatus.trans3to5();
solve(depth + 1);
steps[depth] = preStatus.trans5to3();
solve(depth + 1);
steps[depth] = preStatus.empty3();
solve(depth + 1);
steps[depth] = preStatus.empty5();
solve(depth + 1);
}
private static boolean duplicate(int depth){
for(int i=0 ; i < depth ; i++){
if( steps[i].equals(steps[depth])){
return true;
}
}
return false;
}
private static void paint(int depth){
for(int i = 0; i <= depth; i++){
System.out.print(steps[i]+" ");
}
System.out.println();
}
}
class Status{
int cup3;
int cup5;
public Status(){
}
public Status(Status s){
this.cup3 = s.cup3;
this.cup5 = s.cup5;
}
public Status full3(){
Status newStatus = new Status(this);
newStatus.cup3 = 3;
return newStatus;
}
public Status full5(){
Status newStatus = new Status(this);
newStatus.cup5 = 5;
return newStatus;
}
public Status trans3to5(){
Status newStatus = new Status(this);
if(5 - newStatus.cup5 >= newStatus.cup3){
newStatus.cup5 += newStatus.cup3;
newStatus.cup3 = 0;
}else{
newStatus.cup3 -= (5 - newStatus.cup5);
newStatus.cup5 = 5;
}
return newStatus;
}
public Status trans5to3(){
Status newStatus = new Status(this);
if(newStatus.cup5 <= 3 - newStatus.cup3){
newStatus.cup3 += newStatus.cup5;
newStatus.cup5 = 0;
}else{
newStatus.cup5 -= (3 - newStatus.cup3);
newStatus.cup3 = 3;
}
return newStatus;
}
public Status empty3(){
Status newStatus = new Status(this);
newStatus.cup3 = 0;
return newStatus;
}
public Status empty5(){
Status newStatus = new Status(this);
newStatus.cup5 = 0;
return newStatus;
}
public String toString(){
return "["+this.cup3+"#"+this.cup5+"]";
}
public boolean equals(Object o){
if(o == null){
return false;
}
if(o == this){
return true;
}
if(o instanceof Status){
Status s = (Status)o;
return s.cup3 == this.cup3 && s.cup5 == this.cup5;
}
return false;
}
}