membd

Showing posts with label array pop. Show all posts

Wednesday, September 9, 2015

Reverse Polish notation Calculator using stack (for better understanding oop concept)

<?php

class Stack {
public $array = array();
public $index = -1;

public function isEmpty()
{
if($this->index == -1){
return true;
}else{
return false;
}
}
public function push($element)
{
$this->index++;
$this->array[$this->index] = $element;
}

public function pop()
{
//return $this->array[$this->index--];
if($this->isEmpty()){
echo 'Nothing to pop';
}else{
$element = $this->array[$this->index];
unset($this->array[$this->index]);
$this->index--;
return $element;

}

}
public function calculator($value1, $value2, $operator){
if($operator == "+"){
$result = $value1 + $value2;
} elseif($operator == "-"){
$result = $value1 - $value2;
} elseif($operator == "*"){
$result = $value1 * $value2;
} elseif($operator == "/"){
$result = $value1 / $value2;
}

return $result;
}

}
$stack = new Stack();
if(isset($_POST['numbers'])){
$numbers = trim($_POST['numbers']);
$numbers = explode(' ', $numbers);
foreach ($numbers as $number) {
if(is_numeric($number)) {
$number = intval($number);
$stack->push($number);
}else{
$value2 = $stack->pop();
$value1 = $stack->pop();
$result = $stack->calculator($value1, $value2, $number);
$stack->push($result);
}
}
$result = $stack->pop();
echo $result;
}
?>
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
</head>
<body>
<form method="post" action="">
<input type="text" name="numbers" id="">
<input type="submit" name="submit" id="">
</form>
</body>
</html>

array stack and queue function with initialize array using construct function

<?php
class Stack {
private $stack_array = array();
public $index = -1;

public function __construct($array)
{
$this->stack_array = $array;
$length = count($this->stack_array);
$this->index = $length - 1;
}
public function print_array()
{
print_r($this->stack_array);
}
public function isEmpty()
{
if($this->index == -1){
return true;
}else{
return false;
}
}

public function push($element)
{
$this->index++;
$this->stack_array[$this->index] = $element;
}

public function pop()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
$element = $this->stack_array[$this->index];
unset($this->stack_array[$this->index]);
$this->index--;
}
}

public function pop_from_last()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
$element = $this->stack_array[0];
unset($this->stack_array[0]);
$this->index--;
return $element;
}
}
public function first()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
return $this->stack_array[$this->index];
}
}

public function last()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
return $this->stack_array[0];
}
}

public function get_element($position)
{
if($position >= $this->index + 1){
echo 'position is exceeding the array index';
}else{
$i = $this->index - ($position - 1);
return $this->stack_array[$i];

}
}
}

$stack = new Stack([3, 4, 5, 8]);
$stack->print_array();
echo $stack->index;

Tuesday, September 8, 2015

array stack and queue function in a class to demonstrate push, pop, first, last, pop from last, get element

<?php
class Stack {
private $stack_array = array();
private $index = -1;

public function print_array()
{
print_r($this->stack_array);
}
public function isEmpty()
{
if($this->index == -1){
return true;
}else{
return false;
}
}

public function push($element)
{
$this->index++;
$this->stack_array[$this->index] = $element;
}

public function pop()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
$element = $this->stack_array[$this->index];
unset($this->stack_array[$this->index]);
$this->index--;
}
}

public function pop_from_last()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
$element = $this->stack_array[0];
unset($this->stack_array[0]);
$this->index--;
return $element;
}
}
public function first()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
return $this->stack_array[$this->index];
}
}

public function last()
{
if($this->isEmpty()){
echo 'The array doesn\'t contain any elemnet';
}else{
return $this->stack_array[0];
}
}

public function get_element($position)
{
if($position >= $this->index + 1){
echo 'position is exceeding the array index';
}else{
$i = $this->index - ($position - 1);
return $this->stack_array[$i];

}
}
}

$stack = new Stack();
$stack->push(8);
$stack->push(5);
$stack->push(4);
$stack->push(9);
$stack->push(2);
$stack->print_array();
echo '<br>';
echo $stack->get_element(1);
echo '<br>';
echo $stack->get_element(2);
echo '<br>';
echo $stack->get_element(3);
echo '<br>';
echo $stack->get_element(30);

Monday, September 7, 2015

array stack class to demonstrate push pop first last

<?php
class Stack {
private $array = array(2, 3, 4, 5);
public function print_array(){
print_r( $this->array );
}
public function push_to_array($value){
$this->array[] = $value;
}
public function pop_from_array(){
$count = count($this->array) - 1;
if(empty($this->array[$count])){
echo 'array is empty';
} else{
$pop_value = $this->array[$count];
unset($this->array[$count]);
return $pop_value;
}
}
public function last(){
if(empty($this->array[0])){
return 'array is empty';
} else{
return $this->array[0];
}
}
public function first(){
$count = count($this->array) - 1;
if(empty($this->array[$count])){
return 'array is empty';
} else{
return $this->array[$count];
}
}

}

$array = new Stack();
echo $array->pop_from_array();
$array->print_array();