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PHP Exercises: Compute sum of the prime numbers less than 100

PHP: Exercise-37 with Solution

Write a PHP program to compute the sum of the prime numbers less than 100.

Note: There are 25 prime numbers are there in less than 100.
2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97 and sum of all these numbers is 1060.

Sample Solution: -

PHP Code:

<?php
$primes = array();
$is_prime_no = false;
for ($i = 2; $i<100; $i++) {
     $is_prime_no = true; 
        for ($j = 2; $j<=($i/2); $j++) {
                if ($i%$j==0) {
                          $is_prime_no = false;
                                  break;
                                }
                   }
        if ($is_prime_no) {
               array_push($primes,$i);
                  }
        if (count($primes)==100) {
               break;
                  }
}
echo array_sum($primes)."\n";
?>

Sample Output:

1060       

Flowchart:

Flowchart: Compute sum of the prime numbers less than 100

PHP Code Editor:

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Previous: Write a PHP program to test if a given string occurs at the end of another given string.
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PHP: Tips of the Day

Mutates the original array to filter out the values specified

Example:

<?php
function tips_pull(&$items, ...$params)
{
  $items = array_values(array_diff($items, $params));
  return $items;
}

$items = ['x', 'y', 'z', 'x', 'y', 'z'];
print_r(tips_pull($items, 'y', 'z'));
?>

Output:

Array
(
    [0] => x
    [1] => x
)