46 lines
677 B
PHP
46 lines
677 B
PHP
<?php
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/**
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*
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*/
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namespace Andileco\Util\EvalMath;
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/**
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* Class Stack
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*/
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class Stack
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{
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/**
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* @var array
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*/
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public $stack = array();
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/**
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* @var int
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*/
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public $count = 0;
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public function push($val)
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{
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$this->stack[$this->count] = $val;
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$this->count++;
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}
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public function pop()
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{
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if ($this->count > 0) {
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$this->count--;
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return $this->stack[$this->count];
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}
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return null;
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}
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public function last($n=1)
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{
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$key = $this->count - $n;
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return array_key_exists($key,$this->stack) ? $this->stack[$key] : null;
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}
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}
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