= 4.0.4, PHP 5, PHP 7, PHP 8)gmp_prob_prime — Check if number is " $repe"="" int="" $num,="" prime"說明gmp_prob_prime(gmp|int|string="" probably="">
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      gmp_prob_prime
      
  
      (PHP 4 >= 4.0.4, PHP 5, PHP 7, PHP 8)
      gmp_prob_prime — Check if number is "probably prime"
      

 
      
 
 
      
  
      說明
      
  
      
   gmp_prob_prime(GMP|int|string $num, int $repetitions = 10): int
      

  
      
   The function uses Miller-Rabin's probabilistic test to check if a number is a prime.
  
      
 
      


 
      
  
      參數(shù)
      
  
      
   
      
    
     
      
num
      

     
      

      
      
       The number being checked as a prime.
      
      
      
      GMP 對象或 int ，或數(shù)字string。
       
     
      

    
    
     
      
repetitions
      

     
      

      
      
       Reasonable values
       of repetitions vary from 5 to 10 (default being
       10); a higher value lowers the probability for a non-prime to
       pass as a "probable" prime.
      
      
      
      GMP 對象或 int ，或數(shù)字string。
       
     
      

    
   
      

  
      
 
      


 
      
  
      返回值
      
  
      
   If this function returns 0, num is
   definitely not prime. If it returns 1, then
   num is "probably" prime.  If it returns 2,
   then num is surely prime. 
  
      
 
      


 
      
  
      范例
      
  
      
   
      
    
      示例 #1 gmp_prob_prime() example
      
    
      

      
<?php
      // definitely not a prime
      echo gmp_prob_prime("6") . "\n";

      // probably a prime
      echo gmp_prob_prime("1111111111111111111") . "\n";

      // definitely a prime
      echo gmp_prob_prime("11") . "\n";
      ?>
      

      
    
      

    
      以上例程會輸出：
      
    
      

      0
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