这是我在这里的第一个问题,我希望你能帮助我......
我试图通过三种搜索方式(BFS-DFS-IDS)找到河内问题塔的解决方案,所以我使用由5个变量定义的“州”类whitch:
班级州{
var $tower1 = array(); var $tower2 = array(); var $tower3 = array(); var $depth; var $neighbors = array();
它还有很多功能,其中一个是getneighbors(),它应该用状态邻居填充数组$邻居,它们来自“state”类型
这是函数:
function getneighbors()
{
$temp=$this->copy();
$neighbor1= $this->copy();
$neighbor2= $this->copy();
$neighbor3= $this->copy();
$neighbor4= $this->copy();
$neighbor5= $this->copy();
$neighbor6= $this->copy();
if(!Empty($temp->tower1))
{
if(!Empty($neighbor1->tower2))
{
if(end($neighbor1->tower1) < end($neighbor1->tower2))
{
array_unshift($neighbor1->tower2,array_pop($neighbor1->tower1));
array_push($neighbors,$neighbor1);
}}
else
{
array_unshift($neighbor1->tower2, array_pop($neighbor1->tower1));
array_push($neighbors,$neighbor1);
}
if(!Empty($neighbor2->tower3))
{
if(end($neighbor2->tower1) < end($neighbor2->tower3))
{ array_unshift($neighbor2->tower3, array_pop($neighbor2->tower1));
array_push($neighbors,$neighbor2);
}}
else
{
array_unshift($neighbor2->tower3,array_shift($neighbor2->tower1));
array_push($neighbors,$neighbor2);
}
}
if(!Empty($temp->tower2))
{
if(!Empty($neighbor3->tower1))
{
if(end($neighbor3->tower2) < end($neighbor3->tower1))
{ array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2));
array_push($neighbors,$neighbor3);
}
}
else
{
array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2));
array_push($neighbors,$neighbor3);
}
if(!Empty($neighbor4->tower3))
{
if(end($neighbor4->tower2) < end($neighbor4->tower3))
{ array_unshift($neighbor4->tower1,array_shift($neighbor4->tower2));
array_push($neighbors,$neighbor4);
}
}
else{
array_unshift($neighbor4->tower3,array_shift($neighbor4->tower2));
array_push($neighbors,$neighbor4);
}
}
if(!Empty($temp->tower3))
{
if(!Empty($neighbor5->tower1))
{
if(end($neighbor5->tower3) < end($neighbor5->tower1))
{array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3));
array_push($neighbors,$neighbor5);
}
}
else{
array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3));
array_push($neighbors,$neighbor5);}
if(!Empty($neighbor6->tower2))
{
if(end($neighbor6->tower3) < end($neighbor6->tower2))
{ array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3));
array_push($neighbors,$neighbor6);
}}
else{
array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3));
array_push($neighbors,$neighbor6);}
}
return $neighbors;
}
请注意,toString和equals以及copy也是定义的
现在的问题是,当我调用getneighbors()时,它返回一个空的$ neighbors数组
你能告诉我这个问题吗?答案 0 :(得分:3)
您有一个范围问题。 $neighbors
是一个类变量,而不是PHP全局变量。您引用的任何地方$neighbors
都会将其更改为$this->neighbors
。