codingtests/solutions/ProjectEuler/027/solve.php

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<?php
function is_prime($prime) {
if($prime == 1)
return true;
if($prime == 2)
return true;
$sqrt = sqrt($prime);
for ($i = 3; $i <= $sqrt; $i+=2){
if ($prime%$i == 0) return false;
}
return true;
}
$high = 0;
$max_primes = 0;
for($a=-999; $a<1000; $a++) {
for($b=-999; $b<1000; $b=$b+2) {
$n=0;
while(true) {
echo $n*$n + $a * $n + $b . "\n";
if(!is_prime($n*$n + $a * $n + $b)) {
if($n > $max_primes) {
$max_primes = $n;
echo "max: $n a: $a b: $b\n";
}
break;
}
$n++;
}
}
}