用A算法实现的八数码问题C++源码

用A*算法实现的八数码问题C++源码
#include
#include
#include
#include
#include
#include
//using namespace std;
//定义默认目标状态
static int target[9]={1,2,3,8,0,4,7,6,5};
//八数码类
class EightNum
{
private:
int num[9];
int diffnum;//与目标状态位置不同的数的个数.
int deapth;//派生的深度.
int evalfun;//状态的估价值
public:
EightNum *parent;//生成当前状态的父状态.
EightNum *state_pre;//当前状态前生成状态.
EightNum *state_next;//当前状态后生成状态.
//成员函数声明
EightNum(void);
EightNum(int initnum[9]);
int get_evalfun();
void eval_func();
void getnum(int num1[9]);
void setnum(int num1[9]);
void show(void);
void show_spec(int i);
int null_position(void);
EightNum& operator =(EightNum& NewEightN);
EightNum& operator =(int num2[9]);
int operator ==(EightNum& NewEightN);
int operator ==(int num2[9]);
};//八数码类定义

//八数码类成员函数定义
EightNum::EightNum(void){//初始化数组num[]
for(int i=0;i<9;i++)
num[i]=i;
}

EightNum::EightNum(int initnum[9]){//用输入的数组初始化num[]
for(int i=0;i<9;i++)
num[i]=initnum[i];
}

int EightNum::get_evalfun(){//返回估价值
return evalfun;
}


void EightNum::eval_func(){//估价函数
int i,temp;
temp=0;
for(i=0;i<9;i++){
if(num[i]!=target[i])
temp++;
}
diffnum=temp;
if(this->parent==NULL) deapth=0;
else deapth=this->parent->deapth+1;
evalfun=deapth+temp;
}

void EightNum::getnum(int num1[9]){//取出八数码数值
for(int i=0;i<9;i++)
num1[i]=num[i];
}

void EightNum::setnum(int num1[9]){//写入八数码数值
for(int i=0;i<9;i++)
num[i]=num1[i];
}

void EightNum::show(){//八数码输出函数
for(int i=0;i<9;i++){
cout<if((i+1)%3==0)
cout<<"\n";
}
}

void EightNum::show_spec(int i){//结果步骤输出函数
cout<cout<<"<--";
}

int EightNum::null_position(){//查找空格位置
int i,j;
for(i=0;i<9;i++){
if(num[i]==0)
j=i;
}
return j;
}

EightNum& EightNum::operator =(EightNum& NewEightN){//"="重载,针对八数码类的引用
for(int i=0;i<9;i++)
num[i]=NewEightN.num[i];
diffnum=NewEightN.diffnum;
deapth=NewEightN.deapth+1;
evalfun=diffnum+deapth;
return *this;
}

EightNum& EightNum::operator =(int num2[9]){//"="重载,用于数组赋值
for(int i=0;i<9;i++)
num[i]=num2[i];
return *this;
}

int EightNum::operator ==(EightNum& NewEightN){//"=="重载,用于八数码类中状态的比较
int compere=1;
for(int i=0;i<9;i++)
if(num[i]!=NewEightN.num[i]){
compere=0;
break;
}
if(compere==0) return 0;
else return 1;
}

int EightNum::operator ==(int num2[9]){//"=="重载,用于数组的比较
int compere=1;
for(int i=0;i<9;i++)
if(num[i]!=num2[i]){

compere=0;
break;
}
if(compere==0) return 0;
else return 1;
}
//八数码类函数定义结束

int solve(int num[9],int target[9]){//判断是否有解的函数,利用逆序数的奇偶性来判断
int i,j;
int num_con=0,tar_con=0;
for(i=0;i<9;i++)
for(j=0;jif(num[j]num_con++;
if(target[j]tar_con++;
}
num_con=num_con%2;
tar_con=tar_con%2;
if((num_con==0 && tar_con==0)||(num_con==1 && tar_con==1))
return 1;
else
return 0;
}

//空格移动函数
int moveup(int num[9]){//空格上移
for(int i=0;i<9;i++)
if(num[i]==0) break;
if(i<3) return 0;
else {
num[i]=num[i-3];
num[i-3]=0;
return 1;
}
}

int movedown(int num[9]){//空格下移
for(int i=0;i<9;i++)
if(num[i]==0) break;
if(i>5) return 0;
else {
num[i]=num[i+3];
num[i+3]=0;
return 1;
}
}

int moveleft(int num[9]){//空格左移
for(int i=0;i<9;i++)
if(num[i]==0) break;
if(i==0||i==3||i==6) return 0;
else {
num[i]=num[i-1];
num[i-1]=0;
return 1;
}
}

int moveright(int num[9]){//空格右移
for(int i=0;i<9;i++)
if(num[i]==0) break;
if(i==2||i==5||i==8) return 0;
else {
num[i]=num[i+1];
num[i+1]=0;
return 1;
}
}

int exist(int num[9],EightNum *a){//判断是否重复搜索函数
EightNum *t;
for(t=a;t!=NULL;t=t->parent)
if(*t==num) return 1;//调用"=="进行数组比较
else return 0;
}

EightNum* find(EightNum *s){//寻找估价函数值最小的节点
EightNum *m,*n;
int min=s->get_evalfun();
m=n=s;
for(m=s;m!=NULL;m=m->state_next){
if(min>m->get_evalfun()){
n=m;
min=m->get_evalfun();
}
return n;
}
}

int main(void)//主函数
{
int i,j;
int flag;
int num[9];
int error;

do{//输入判断
error=0;
cout<<"请输入八数码问题的初始状态(用0代表空格,中间用空格隔开):"<for(i=0;i<9;i++){
flag=0;
cin>>num[i];
for(j=0;jif(num[j]==num[i])
flag=1;
if(num[i]<0||num[i]>8||flag==1){
error++;
}
}
if(error!=0)
cout<<"输入数据错误!请重新输入!"<}while(error!=0);

cout<<"是否改变默认的目标状态?(y/n)";
char input;
cin>>input;
int error1;
if(input=='y'||input=='Y'){
do{
error1=0;
cout<<"请输入新的目标状态(用0代表空格):"<for(i=0;i<9;i++){
flag=0;
cin>>target[i];
for(j=0;jif(target[j]==target[i])
flag=1;
if(target[i]<0||target[i]>9||flag==1){
error1++;
}
}
if(error1!=0)
cout<<"输入数据错误!请重新输入!"<}while(error1!=0);
}

//实例化初始状态和目标状态,并输出.
EightNum start(num),Target(target);
start.parent=start.state_next=start.state_pre=NULL;
start.eval_func();
cout<<"初始状态为:"<start.show();
cout<<"目标状态为:"<

l;
Target.show();
//判断是否有解
int m=solve(num,target);
if(m==0){
cout<<"此状态无解!"<return 0;
}

//进入A*算法搜索
double time;
clock_t startt,finisht;
int ok=0;//结束标识位
int space=0;//所耗费空间

startt=clock();//开始时间
EightNum *BestNode=&start,*Node=&start,*New8Num,*r;
while(BestNode!=NULL&&ok!=1)
{
BestNode=find(Node);
if(*BestNode==Target){//调用"=="操作符
ok=1;
break;
}
r=BestNode->state_pre;

//生成向上移的节点
BestNode->getnum(num);
if(moveup(num) && !exist(num,BestNode)){
New8Num=new EightNum;
New8Num->setnum(num);
New8Num->parent=BestNode;
New8Num->eval_func();
New8Num->state_pre=r;
if(r==NULL)
Node=New8Num;
else
r->state_next=New8Num;
r=New8Num;
space++;
}

//生成向下移的节点
BestNode->getnum(num);
if(movedown(num) && !exist(num,BestNode)){
New8Num=new EightNum;
New8Num->setnum(num);
New8Num->parent=BestNode;
New8Num->eval_func();
New8Num->state_pre=r;
if(r==NULL)
Node=New8Num;
else
r->state_next=New8Num;
r=New8Num;
space++;
}

//生成向左移的节点
BestNode->getnum(num);
if(moveleft(num) && !exist(num,BestNode)){
New8Num=new EightNum;
New8Num->setnum(num);
New8Num->parent=BestNode;
New8Num->eval_func();
New8Num->state_pre=r;
if(r==NULL)
Node=New8Num;
else
r->state_next=New8Num;
r=New8Num;
space++;
}

//生成向右移的节点
BestNode->getnum(num);
if(moveright(num) && !exist(num,BestNode)){
New8Num=new EightNum;
New8Num->setnum(num);
New8Num->parent=BestNode;
New8Num->eval_func();
New8Num->state_pre=r;
if(r==NULL)
Node=New8Num;
else
r->state_next=New8Num;
r=New8Num;
space++;
}

r->state_next=BestNode->state_next;
if(BestNode->state_next!=NULL)
BestNode->state_next->state_pre=r;
BestNode->state_next=BestNode->state_pre=NULL;
}
finisht=clock();

//输出搜索结果
if(ok==1){
time=(double)(finisht-startt)*1000/CLOCKS_PER_SEC;
EightNum *p,*q=NULL;
int step=0;
for(p=BestNode->parent;p!=NULL;p->parent){
if(step==0){
i=8;
p->show_spec(i);
i=p->null_position();
}
else{
p->show_spec(i);
i=p->null_position();
}
if (step==8||step==18||step==28||step==38||step==48)
cout<<"\n";
step++;
}

cout<<"\nA*算法处理结果：所耗时间:";
cout<cout<<"ms, ";
cout<<"所耗空间:";
cout<cout<<"块, ";
cout<<"最短路径步数:";
cout<cout<<"步 !\n";
}
else
cout<<"\nA*算法无法找到最短路径!\n";
}