Difference between revisions of "Tutorial"
From Ubcacm
(→Floating Point) |
|||
| (One intermediate revision by one other user not shown) | |||
| Line 1: | Line 1: | ||
| + | == Compiling the Program == | ||
| + | === C === | ||
| + | gcc <input.c> -o output -Wall | ||
| + | === C++ === | ||
| + | g++ <input.c> -o output -Wall | ||
| + | Note that attempting to compile a C++ file with '''gcc''' will fail with ''' undefined reference to `__gxx_personality_v0'''' | ||
| + | |||
| + | '''-Wall''' turns on all compiler warnings, It is not necessary, but often useful to catch silly mistakes in the code. | ||
| + | |||
| + | === Java === | ||
| + | javac <input.java> | ||
| + | |||
== Data Representation == | == Data Representation == | ||
=== Numbers === | === Numbers === | ||
| Line 21: | Line 33: | ||
* This is slow, but infinitely precise. | * This is slow, but infinitely precise. | ||
==== Floating Point ==== | ==== Floating Point ==== | ||
| + | * [http://www.cygnus-software.com/papers/comparingfloats/comparingfloats.htm Comparing Floating Point numbers] | ||
| + | |||
=== Strings === | === Strings === | ||
=== Structures === | === Structures === | ||
=== Classes === | === Classes === | ||
Latest revision as of 03:52, 18 February 2007
Contents
Compiling the Program
C
gcc <input.c> -o output -Wall
C++
g++ <input.c> -o output -Wall
Note that attempting to compile a C++ file with gcc will fail with undefined reference to `__gxx_personality_v0'
-Wall turns on all compiler warnings, It is not necessary, but often useful to catch silly mistakes in the code.
Java
javac <input.java>
Data Representation
Numbers
Boolean
Integers
Fixed Length
- char: 8 bits in C/C++, 16 bits in Java
- int: 32 bits
- long: 32 bits in C/C++, 64 bit in Java
- long long: 64 bits in C/C++, GCC only. (__int64 in Microsoft C++)
An n-bit signed integer can represent values int the range [-2n-1, 2n-1 - 1].
An unsigned integer can represent values in the range [0, 2n - 1] (Not available in Java)
Values are represented in 2's complement (mod 2n) during overflow.
Division rounds towards 0
- (-5) / 3 = -1
- 7 / 3 = 2
- 1 / 2 = 0
Arbitrary Length
Java has BigInteger
- This is slow, but infinitely precise.
