PHP | Check if a number is armstrong number

Given a number, we need to check whether it is an armstrong number or not in PHP. An Armstrong number is the one whose value is equal to the sum of the cubes of its digits.

Examples:

Input : 407
Output : Yes
407 = (4*4*4) + (0*0*0) + (7*7*7)  
    = 64 + 0 + 343  
    = 407  

Input : 303
Output : No

Recommended: Please try your approach on {IDE} first, before moving on to the solution.

Approach: For every digit r in input number x, compute r³. If sum of all such values is equal to n, then print “Yes”, else “No”.

<?php 
// PHP code to check wether a number is  
// armstrong number or not 
  
// function to check whether the number is  
// armstrong number or not 
function armstrongCheck($number){ 
    $sum = 0;   
    $x = $number;   
    while($x != 0)   
    {   
        $rem = $x % 10;   
        $sum = $sum + $rem*$rem*$rem;   
        $x = $x / 10;   
    }   
      
    // if true then armstrong number 
    if ($number == $sum) 
        return 1; 
      
    // not an armstrong number     
    return 0;     
} 
  
// Driver Code 
$number = 407; 
$flag = armstrongCheck($number); 
if ($flag == 1) 
    echo "Yes"; 
else
    echo "No"
?> 

Output:

Yes

Time Complexity: O(num), where num is the number of digits in the given number.

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