Java BigInteger添加看起来不对

Question

我有两个字节数组,我试图添加使用

BigInteger n1=new BigInteger(byte[] a1);
BigInteger n2=new BigInteger(byte[] a2);
BigInteger sum=a1.add(a2);
byte[] as=sum.toByteArray();

这就是我得到的:

a1=4A4A3E502602CE0C3D1792D5A2C6BADFE701E5C668FBE1D92F19923CD2A5143B
a2=FFE735AE9FB702A6C08D3ED57CB6CCF7CBB74F6F8D3F820A837A9775AF953F0D
as=4A3173FEC5B9D0B2FDA4D1AB1F7D87D7B2B93535F63B63E3B29429B2823A5348

查看最重要的字节,添加0x4A和0xFF会生成丢失的进位.我希望添加两个32字节整数将导致33字节整数(这种情况,因为有一个进位).

Answer 1

你确定你的字节数组的内容a1和a2？

BigInteger b1 = new BigInteger("4A4A3E502602CE0C3D1792D5A2C6BADFE701E5C668FBE1D92F19923CD2A5143B", 16);
BigInteger b2 = new BigInteger("FFE735AE9FB702A6C08D3ED57CB6CCF7CBB74F6F8D3F820A837A9775AF953F0D", 16);
BigInteger c = b1.add(b2);
System.out.println(c.toString(16));

生产:

4a4a3e502602ce0c3d1792d5a2c6badfe701e5c668fbe1d92f19923cd2a5143b
ffe735ae9fb702a6c08d3ed57cb6ccf7cbb74f6f8d3f820a837a9775af953f0d
14a3173fec5b9d0b2fda4d1ab1f7d87d7b2b93535f63b63e3b29429b2823a5348

随着预期的携带.