php/skripty/prvocisla.php

   1 <?php
   2
   3 //FUNCTION IS_PRIME()
   4
   5 function is_prime ($num) {
   6
   7   if($num < 2) { return (0); }
   8   if ( ($num > 2) && (($num % 2) == 0) ) { return (0); }
   9   $i = 2;
  10   while ($i < $num) {
  11     if ( ($num % $i) == 0 ) { return (0); }
  12     $i++;
  13   }
  14   return (1);
  15 }
  16
  17 //CODE
  18
  19 //Prvocisla: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, \85
  20 //echo(is_prime(1)."\n".(7%2)); //Debug
  21
  22 //Settings
  23 $min = 1;
  24 $max = 3000;
  25
  26 //Logic
  27 $total_primes = 0;
  28 while ($min <= $max) {
  29   if(is_prime($min)) {
  30   echo($min."\n"); //Show all primes
  31   $total_primes++; //Count all primes
  32   }
  33 $min++;
  34 }
  35
  36 //Output
  37 echo("\nPrimes total: ".$total_primes."\n"); //Total number of primes
  38
  39 ?>