- var_dump: documentation ( source)
- ceil: documentation ( source)
- sqrt: documentation ( source)
<?php
function prim($n) {
if ( $n == 1 )
return false;
if ( $n == 2)
return true;
if ( $n % 2 == 0 )
return true;
for ( $i = 3; $i < ceil(sqrt($n)); $i+=2) {
if ( $n % $i == 0 )
return true;
}
return false;
}
var_dump(prim(1));
var_dump(prim(2));
var_dump(prim(3));
var_dump(prim(4));
var_dump(prim(5));
var_dump(prim(6));
var_dump(prim(7));
var_dump(prim(8));
var_dump(prim(9));
var_dump(prim(11));