Java BigInteger isProbablePrime()用法及代码示例

java.math.BigInteger.isProbablePrime(int surety)方法用于判断此BigInteger可能是素数还是绝对是合成的。此方法检查当前BigInteger上是否有素数或复合数，由此方法将被调用，并返回一个布尔值。如果此BigInteger可能是素数，则返回true；如果绝对是复合值，则返回false。如果确定

用法:

public boolean isProbablePrime(int certainty)

参数:该方法接受强制性参数确定性，该确定性是对用户可接受的不确定性的度量。这是由于BigInteger是一个非常大的数字，并且很难准确地确定它是否是素数。因此可以说，此方法基于阈值(1- 1/2)检查此BigInteger的质数。^certainty)。

返回值：此方法返回一个布尔值，该值指示此BigInteger是否为素数。如果此BigInteger可能是素数，则返回true；如果绝对是复合值，则返回false。

下面的程序用于说明BigInteger的isProbablePrime()方法。

范例1：

// Java program to demonstrate 
// isProbablePrime() method of BigInteger 
  
import java.math.BigInteger; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Boolean variable to store the result 
        boolean result; 
  
        // Creates one BigInteger object 
        BigInteger a 
            = new BigInteger( 
                "95848961698036841689418631330196"); 
  
        // When certainty is one, 
        // it will check number for prime or composite 
        result = a.isProbablePrime(1); 
        System.out.println(a.toString() 
                           + " with certainty 1 "
                           + result); 
  
        // When certainty is zero, 
        // it is always true 
        result = a.isProbablePrime(0); 
        System.out.println(a.toString() 
                           + " with certainty 0 "
                           + result); 
  
        // When certainty is negative, 
        // it is always true 
        result = a.isProbablePrime(-1); 
        System.out.println(a.toString() 
                           + " with certainty -1 "
                           + result); 
    } 
}

输出：

95848961698036841689418631330196 with certainty 1 false
95848961698036841689418631330196 with certainty 0 true
95848961698036841689418631330196 with certainty -1 true

范例2：

// Java program to demonstrate 
// isProbablePrime() method of BigInteger 
  
import java.math.BigInteger; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Boolean variable to store the result 
        boolean result; 
  
        // Creates one BigInteger object 
        BigInteger a 
            = new BigInteger( 
                "654561561356879113561"); 
  
        // When certainty is one, 
        // it will check number for prime or composite 
        result = a.isProbablePrime(1); 
        System.out.println(a.toString() 
                           + " with certainty 1 "
                           + result); 
  
        // When certainty is zero, 
        // it is always true 
        result = a.isProbablePrime(0); 
        System.out.println(a.toString() 
                           + " with certainty 0 "
                           + result); 
  
        // When certainty is negative, 
        // it is always true 
        result = a.isProbablePrime(-1); 
        System.out.println(a.toString() 
                           + " with certainty -1 "
                           + result); 
    } 
}

输出：

654561561356879113561 with certainty 1 false
654561561356879113561 with certainty 0 true
654561561356879113561 with certainty -1 true

参考： https://docs.oracle.com/javase/9/docs/api/java/math/BigInteger.html#isProbablePrime(int)

相关用法

注：本文由纯净天空筛选整理自Rajnis09大神的英文原创作品 BigInteger isProbablePrime() Method in Java with Examples。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。