PHP数组组合
我有一个由7个数字组成的数组(1,2,3,4,5,6,7),我想制作5个数字对,例如(1,2,3,4,5),(1,2,3
,4,6,),(1,2,3,4,7)。(1,2,3,4,5)等于(4,5,3,1,2)
我想知道PHP中是否有函数或任何可以执行此操作的算法?我不知道从哪里开始。你能帮助我吗 ?
我想将7个给定数字的所有组合(它们从数组中取出)放入5个插槽中,而无视顺序
回答:
如果链接断开,这里是代码。
class Combinations implements Iterator{
protected $c = null;
protected $s = null;
protected $n = 0;
protected $k = 0;
protected $pos = 0;
function __construct($s, $k) {
if(is_array($s)) {
$this->s = array_values($s);
$this->n = count($this->s);
} else {
$this->s = (string) $s;
$this->n = strlen($this->s);
}
$this->k = $k;
$this->rewind();
}
function key() {
return $this->pos;
}
function current() {
$r = array();
for($i = 0; $i < $this->k; $i++)
$r[] = $this->s[$this->c[$i]];
return is_array($this->s) ? $r : implode('', $r);
}
function next() {
if($this->_next())
$this->pos++;
else
$this->pos = -1;
}
function rewind() {
$this->c = range(0, $this->k);
$this->pos = 0;
}
function valid() {
return $this->pos >= 0;
}
protected function _next() {
$i = $this->k - 1;
while ($i >= 0 && $this->c[$i] == $this->n - $this->k + $i)
$i--;
if($i < 0)
return false;
$this->c[$i]++;
while($i++ < $this->k - 1)
$this->c[$i] = $this->c[$i - 1] + 1;
return true;
}
}
foreach(new Combinations("1234567", 5) as $substring)
echo $substring, ' ';
12345 12346 12347 12356 12357 12367 12456 12457 12467 12567 13456 13457 13467
13567 14567 23456 23457 23467 23567 24567 34567
以上是 PHP数组组合 的全部内容, 来源链接: utcz.com/qa/424439.html