Converting Hexdecimal numbers....

[Narasimha Rao B.]

Hi,
1) Can, any of you explain how to convert big Hex decimal numbers to decimal. For ex, how will you convert 0xffffffc9 to decimal number.
2)
byte b = 0; int i=0;
Is there any short cut method is there to solve the below expression,
b = (byte)(b + (b - (i = 0xffffffc9)))
Thanks in Advance....

[Ryan Wilson]

byte b = 0; int i=0;
b = (byte)(b + (b - (i = 0xffffffc9)))
0xffffffc9 is going to be negative because the leftmost bit is 1. (f = 1111)
so the number is going to be 111........11001001
because c = 1100 and 9 = 1001.
Flip the bits and add 1.
000...........00110110 + 1 = 000....00110111 = -55
b = (byte)(b + (b - (-55)))
b = (byte)(b + 55)
b = (byte)(0 + 55)
b = 55
I hope this helps

[Bert Bates]

Narasimha -
First here's a link that might help...
http://www.coderanch.com/t/241326/java-programmer-SCJP/certification/Converting-Hexadecimal-literals
The key points are:
1 - For anyone new to JavaRanch - the exam won't ask you to convert big hex or octal or binary numbers!
2 - The exam WILL ask you to understand how two's complement numbers are stored, and how the >>, >>>, << operators affect these two's complement numbers.

- Bert
UnderSecretary to the Minister of Keep your Focus

[Jessica Sant]

if you need some more info -- check out our handy dandy search feature. I did a search for "convert hexadecimal" and got a lot of good hits.
Enjoy!