PHP Interview Question

Write the code to calculate sum of each digit in PHP.

<?php  
$num = 12345;  
$sum=0; $rem=0;  
  for ($i =0; $i<=strlen($num);$i++)  
 {  
  $rem=$num%10;  
   $sum = $sum + $rem;  
   $num=$num/10;  
  }  
 echo "Sum of digits 12345 is $sum";  
 ?>  

Output:

Sum of digits 12345 is 15

Write the Program to calculate Even Odd Program in PHP

<?php  
$number=28462;  
if($number%2==0)  
{  
 echo "$number is Even Number";   
}  
else  
{  
 echo "$number is Odd Number";  
}   
?>  

Output:

28462 is Even Number

Write the Program in PHP to calculate the given number is Prime number or not ?

Here, We’ll print first 15 prime numbers.

<?php  
$count = 0;  
$num = 2;  
while ($count < 15 )  
{  
$div_count=0;  
for ( $i=1; $i<=$num; $i++)  
{  
if (($num%$i)==0)  
{  
$div_count++;  
}  
}  
if ($div_count<3)  
{  
echo $num." , ";  
$count=$count+1;  
}  
$num=$num+1;  
}  
?>  

Output:

2,3,5,7,11,13,17,19,23,29,31,37,41,43,47

Write the code to Print Table of a Number

Here , We’ll print the table of 3.

<?php    
define('a', 3);   
for($i=1; $i<=10; $i++)   
{   
  echo $i*a;   
  echo '<br>';     
}  
?>  

Output:

3
6
9
12
15
18
21
24
27
30

Write the code to Factorial in PHP

<?php  
$num = 4;  
$factorial = 1;  
for ($x=$num; $x>=1; $x--)   
{  
  $factorial = $factorial * $x;  
}  
echo "Factorial of $num is $factorial";  
?>  

Output:

Factorial of 4 is 24