Java Java () 方法与示例

Java .lang.Long.reverse()是Java中的一个内置函数，它返回通过反转指定long 值的二进制补码表示中的位的顺序而获得的值。

句法：

public static long reverse(long num) 
Parameter :
num - the number passed
Returns : 
the value obtained by reversing the order of the bits in the 
two's complement binary representation of the specified long value.

例子：

Input : 254 
Output : 9151314442816847872

Input : 8
Output : 1152921504606846976

下面的程序说明了Java.lang.Long.reverse()函数：

程序 1：

// Java program that demonstrates the
// Long.reverse() function
  
// include lang package
import java.lang.*;
  
public class GFG {
  
public static void main(String[] args)
    {
  
        long l = 8;
  
        System.out.println("The number after reversing bit= "
                           + Long.reverse(l));
  
        l = 254;
        System.out.println("The number after reversing bit= "
                           + Long.reverse(l));
    }
}

输出：

The number after reversing bit= 1152921504606846976
The number after reversing bit= 9151314442816847872

程序 2：当传递一个负数时

// Java program that demonstrates the
// Long.reverse() function
// negative number
  
// include lang package
import java.lang.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        long l = -8;
  
        System.out.println("The number after reversing bit= "
                           + Long.reverse(l));
  
        l = -254;
        System.out.println("The number after reversing bit= "
                           + Long.reverse(l));
    }
}

输出：

The number after reversing bit= 2305843009213693951
The number after reversing bit= 4683743612465315839

程序 3：当传递一个十进制数时

// Java program that demonstrates the
// Long.reverse() function
// decimal number
  
// include lang package
import java.lang.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        System.out.println("The number after reversing bit= "
                           + Long.reverse(11.34));
    }
}

输出：

prog.java:16: error: incompatible types: possible lossy conversion from double to long
                           + Long.reverse(11.34));

程序 4 ：当传递一个字符串数字时

// Java program that demonstrates the
// Long.reverse() function
// string number
  
// include lang package
import java.lang.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        System.out.println("The number after reversing bit= "
                           + Long.reverse("12"));
    }
}

输出：

prog.java:16: error: incompatible types: String cannot be converted to long
                           + Long.reverse("12"));