Java中的整数最低OneBit()方法

Java.lang 的 Integer.lowestOneBit() 方法是一个内置函数，它返回一个 int 值，在指定 int 值中的最低位（即最右边）一位的位置，最多只有一位.如果指定的值在其二进制补码表示中没有一位，则此方法将返回零，即。如果数字的二进制表示等于零。
句法：

public static int lowestOneBit(int a)

参数：该方法采用一个整数类型的参数a ，该参数是指要返回其最低位或要对其执行操作的值。
Returns ：该方法可以返回两种类型的值：

• 返回一个具有单个 1 位的整数值，位于指定值中最低位的位置
• 如果指定的值等于零，则返回零。

例子：

Input: 157
Output: Lowest one bit = 1

Input: 0
Output: Lowest one bit = 0

Explanation:
Consider any integer a = 10
Binary Representation = 0000 1010
Lowest bit(at 1) i.e.0000 0010
so result = 2^1=2

下面的程序说明了Java.lang.Integer.lowestOneBit() 方法：
程序 1：对于正数。

java

// Java program to illustrate the
// java.lang.Integer.lowestOneBit() method
import java.lang.*;
 
public class Geeks {
 
    public static void main(String[] args)
    {
 
        int a = 157;
        System.out.println("Given Number = " + a);
 
        // Returns an int value with at most a single one-bit
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
 
        a = 64;
        System.out.println("Given Number = " + a);
 
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
 
        // Here it will return 0 since the number is itself zero
        a = 0;
        System.out.println("Given Number = " + a);
 
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
    }
}

输出：

Given Number = 157
Lowest one bit = 1
Given Number = 64
Lowest one bit = 64
Given Number = 0
Lowest one bit = 0

程序 2：对于负数。

Java

// Java program to illustrate the
// java.lang.Integer.lowestOneBit() method
import java.lang.*;
 
public class Geeks {
 
    public static void main(String[] args)
    {
 
        int a = -157;
        System.out.println("Given Number = " + a);
 
        // It will return an int value with at most a single one-bit
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
        a = -17;
        System.out.println("Given Number = " + a);
 
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
    }
}

输出：

Given Number = -157
Lowest one bit = 1
Given Number = -17
Lowest one bit = 1

程序 3：对于十进制值和字符串。
注意：当十进制值和字符串作为参数传递时，它会返回编译时错误消息。

Java

// Java program to illustrate the
// java.lang.Integer.lowestOneBit() method
import java.lang.*;
 
public class Geeks {
 
    public static void main(String[] args)
    {
 
        // Decimal value is given
        int a = 71.57;
        System.out.println("Given Number = " + a);
 
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
 
        // String is passed
        a = "12";
        System.out.println("Given Number = " + a);
 
        System.out.print("Lowest one bit = ");
        System.out.println(Integer.lowestOneBit(a));
    }
}

输出：

prog.java:10: error: incompatible types: possible lossy conversion from double to int
    int a = 71.57;
            ^
prog.java:17: error: incompatible types: String cannot be converted to int
    a = "12";
        ^
2 errors