O()

(oh of) fn. A computer science notation for describing the computational complexity of an algorithm in shorthand. Many algorithms are O(n), meaning they require a number of CPU cycles in proportion to the number, n, of data elements to be manipulated. For example, algorithms that require 2n + 4 and 45n + 340, respectively, are both O(n). Any algorithm that is polynomial in nature is O(n ^d) where d is the degree of the polynomial. Many algorithms are O(log2 n), O(ln n), or O(n ²); others, by contrast, are NP-incomplete.

obfuscated C

n. A yearly contest in which the goal is to write the cutest, most confusing, least expected, and most bizarre C code. Ironically, the contest has guidelines, rather like the standards they seem to disavow. The official goals are

• to write the most obscure/obfuscated C program using the guidelines,

• to show the importance of programming style in an ironic way,

• to stress C compilers with unusual code,

• to illustrate some of the subtleties of C, and

• to provide a safe forum for poor C code.

Some pundits suggest that the very existence of this contest is a condemnation of C, the programmers who embrace obfuscation, or both.

Further Reading: The contest website is http://www.ioccc.org.

objdump

See binutils.

object

n. A run-time realization of a class. Though there may be more than one object of the same type, all generally share the same code. Each object has its own unique data, on which that...