Java.math.BigInteger.getLowestSetBit()方法實例

 java.math.BigInteger.getLowestSetBit()返回BigInteger最右邊的(最低階)的一個1比特位(零比特到最右邊的1位的權數)的索引。如果此BigInteger包含無比特位，它返回-1。它計算(this==0? -1 : log2(this & -this)).

聲明

以下是java.math.BigInteger.getLowestSetBit()方法的聲明

public int getLowestSetBit()

參數

• NA

返回值

此方法返回BigInteger最右邊的1位的索引。

異常

• NA

例子

下面的例子顯示math.BigInteger.getLowestSetBit()方法的用法

package com.yiibai; import java.math.*; public class BigIntegerDemo { public static void main(String[] args) { // create 2 BigInteger objects BigInteger bi1, bi2; // create 2 int objects int i1, i2; // assign values to bi1, bi2 bi1 = new BigInteger("8");//1000 bi2 = new BigInteger("7");//0111 // perform getLowestSetBit on bi1, bi2 i1 = bi1.getLowestSetBit(); i2 = bi2.getLowestSetBit(); String str1 = "Index of rightmost one bit in " +bi1+ " is " +i1; String str2 = "Index of rightmost one bit in " +bi2+ " is " +i2; // print i1, i2 values System.out.println( str1 ); System.out.println( str2 ); } }

讓我們編譯和運行上面的程序，這將產生以下結果：

Index of rightmost one bit in 8 is 3 Index of rightmost one bit in 7 is 0