Mega Code Archive
A stack with type restricted to int
<![CDATA[
<?
class IntStack {
var $the_stack;
var $count = 0;
function push ($intvar) {
if (is_integer($intvar)) {
$this->the_stack[$this->count] = $intvar;
$this->count++;
print("Push of $intvar succeeded.<BR>");
} else {
print("Hey, IntStack is for ints only!<BR>");
}
}
function pop () {
if ($this->count > 0) {
$this->count--; // decrement count
$top = $this->the_stack[$this->count];
return($top);
} else {
print("Hey, the stack is empty!<BR>");
}
}
}
$my_stack = new IntStack;
$my_stack->push(1);
$my_stack->push(49);
$my_stack->push("A");
$pop_result = $my_stack->pop();
print("Top of the stack was $pop_result<BR>");
$pop_result = $my_stack->pop();
print("Top of the stack was $pop_result<BR>");
$pop_result = $my_stack->pop();
print("Top of the stack was $pop_result<BR>");
?>
]]>