PHP program to compute the sum of first n given prime numbers.

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<?php
$max = 105000;
$arr = new \SplFixedArray($max + 1);
for ($i = 2; $i <= $max; $i++) {
    $arr[$i] = 1;
}
for ($i = 2, $len = sqrt($max); $i <= $len; $i++) {
    if (!$arr[$i]) {
        continue;
    }
    for ($j = $i, $len2 = $max / $i; $j <= $len2; $j++) {
        $arr[$i * $j] = 0;
    }
} 
while (($line = trim(fgets(STDIN))) !== '0') {
    $n = (int)$line;
    $result = 0;
    $cnt = 0;
    for ($i = 2; $i <= $max; $i++) {
        if ($cnt === $n) {
            break;
        } elseif ($arr[$i]) {
            $result += $i;
            $cnt++;
        }
    }
    echo "Sum of first ".$n." prime numbers:";
    echo $result, PHP_EOL;
}
?>


Output:
25
0

Sum of first 25 prime numbers:1060

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