Difference between revisions of "Interview Questions"

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==Some Translation==
 
==Some Translation==
−
n! Multiplicative
+
n! Factorial
 +
 
 
==Object-oriented programming==
 
==Object-oriented programming==
 
Check here [[Interview_Questions(OOP)]]
 
Check here [[Interview_Questions(OOP)]]
 +
==C++ Interview==
 +
[[C++ interview]]
 +
==Javascript/Jquery==
 +
[[AJAX&Jquery]]<br>
 +
[http://{{SERVERNAME}}/downloads/designpattern/ Design Pattern]
 +
 
==Algorithm Interview Problems==
 
==Algorithm Interview Problems==
 
[[Algorithm Problems]]<br>
 
[[Algorithm Problems]]<br>
 +
==Data Structure==
 
[[All about Binary search tree]]<br>
 
[[All about Binary search tree]]<br>
 
[[All about Linked List]]<br>
 
[[All about Linked List]]<br>
 +
[[Heap & Heap Sort]]<br>
 +
[[TRIE]]<br>
 +
[[Algorithm Sorting]]<br>
  
 
==Regular Expression ==
 
==Regular Expression ==
 
http://www.zytrax.com/tech/web/regex.htm
 
http://www.zytrax.com/tech/web/regex.htm
−
 
−
==C/C++==
 
−
===ArrayList Vs LinkedList===
 
−
ArrayList: fast random access<br>
 
−
slow at delete<br>
 
−
memory fill up issue<br>
 
−
LinkedList: slow random access<br>
 
−
quick delete<br>
 
−
no memory fill up issue<br>
 
−
complex data structure<br>
 
  
 
==PHP==
 
==PHP==
−
===abstract class===
+
[[PHP interview]]
−
Can not be Instantiable.(cannot become instant. Can only be inherited)<br>
+
==Java==
−
<pre>
+
[[Java interview]]
−
abstract class Fruit {
+
==Python==
−
private $color;
+
[[Python interview]]
−
 
+
−
abstract public function eat()
+
−
 
+
−
public function setColor($c) {
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−
  $this->color = $c;
+
−
}
+
−
}
+
−
</pre>
+
−
===Single or Double Quotes?===
+
−
<pre>
+
−
//Sometimes people use double quotes in PHP to avoid having to use the period to separate code. For example, you could write:
+
−
$color='red';
+
−
echo "I have a $color shirt on today<br/>";
+
−
//Faster however is not always better. A better way to write this code would be:
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−
echo 'I have a ' .$color. ' shirt on today<br/>';
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−
echo 'I have a $color shirt on today<br/>';
+
−
</pre>
+
−
Output:
+
−
<pre>
+
−
I have a red shirt on today
+
−
I have a red shirt on today
+
−
I have a $color shirt on today
+
−
</pre>
+
−
===Avoid Mysql Injection===
+
−
<pre>
+
−
$_POST['username'] = 'aidan';
+
−
$_POST['password'] = "' OR ''='";
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−
$query = "SELECT * FROM users WHERE user='{$_POST['username']}' AND password='{$_POST['password']}'";
+
−
$passwd=mysql_real_escape_string($_POST['password']);
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−
$passwd1=addslashes($_POST['password']);
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−
echo $passwd."<br />";
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−
echo $passwd1."<br />";
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−
echo ($query);
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−
</pre>
+
−
Output
+
−
<pre>
+
−
\' OR \'\'=\'
+
−
\' OR \'\'=\'
+
−
SELECT * FROM users WHERE user='aidan' AND password='' OR ''=''
+
−
</pre>
+
−
This would allow anyone to log in without a valid password.
+
−
 
+
−
==JavaScript==
+
−
Closure.
+
−
<pre>
+
−
<script>
+
−
function say667() {
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  // Local variable that ends up within closure
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−
  var num = 666;
+
−
 
+
−
  //var sayAlert = function() { alert(num); }
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  return function() { num++; alert(num); };
+
−
}
+
−
 
+
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var sayNumba = say667();
+
−
sayNumba();
+
−
sayNumba();
+
−
</script>
+
−
</pre>
+
−
The example will keep var num in the memory. alert 667 and 668 on each call;
+
−
==Swap 2 numbers in one line==
+
−
<pre>
+
−
//swap
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−
$a=10;
+
−
$b=20;
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$a=$a+$b-($b=$a);
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−
echo $a." and ". $b."\n";
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−
// output 20 and 10
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−
$a^=$b^=$a^=$b; //This has a bug. You cannot do things like this $a^=$a^=$a^=$a
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echo $a." and ". $b;
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//output 10 and 20
+
−
</pre>
+
−
==Calculate degree between hour and minute hand==
+
−
<pre>
+
−
<?php
+
−
$time=array();
+
−
$time['h']=12;
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−
$time['m']=15;
+
−
$time['s']=30;
+
−
function clockDegree($time){
+
−
$mPercent=((float)$time['m']+((float)$time['s']/60.0))/60.0;
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$mDegree=$mPercent*360;
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−
$hdegree=((int)$time['h']%12+(float)$mPercent)/12.0*360;
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−
echo abs($mDegree-$hdegree);
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−
}
+
−
clockDegree($time);
+
−
</pre>
+

Latest revision as of 00:27, 17 March 2015

Some Translation

n! Factorial

Object-oriented programming

Check here Interview_Questions(OOP)

C++ Interview

C++ interview

Javascript/Jquery

AJAX&Jquery
Design Pattern

Algorithm Interview Problems

Algorithm Problems

Data Structure

All about Binary search tree
All about Linked List
Heap & Heap Sort
TRIE
Algorithm Sorting

Regular Expression

http://www.zytrax.com/tech/web/regex.htm

PHP

PHP interview

Java

Java interview

Python

Python interview

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