# decrement

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**Algorithm examples**— This article Algorithm examples supplements Algorithm and Algorithm characterizations. = An example: Algorithm specification of addition m+n =Choice of machine model:This problem has not been resolved by the mathematics community. There is no… …82

**Counter machine reference model**— The Counter machine s reference model is a set of choices and conventions to be used with the Counter machine and other model variants of the Register machine concept. It permits comparisons between models, and serves a didactic function with… …83

**Reference counting**— In computer science, reference counting is a technique of storing the number of references, pointers, or handles to a resource such as an object or block of memory. It is typically used as a means of deallocating objects which are no longer… …84

**IBM 7090**— The IBM 7090 was a second generation transistorized version of the earlier IBM 709 vacuum tube mainframe computers and was designed for large scale scientific and technological applications . The 7090 was the third member of the IBM 700/7000… …85

**Unary operation**— In mathematics, a unary operation is an operation with only one operand, i.e. a single input. Specifically, it is a function where A is a set. In this case f is called a unary operation on A. Common notations are prefix notation (e.g. +, −, not) …86

**Semaphore (programming)**— For other uses, see Semaphore (disambiguation). In computer science, a semaphore is a variable or abstract data type that provides a simple but useful abstraction for controlling access by multiple processes to a common resource in a parallel… …87

**CAR and CDR**— Introduced in the Lisp programming language, car (pronEng|ˈkɑr, just like the English word car ) and cdr (IPA|/ˈkʌdər/ or IPA|/ˈkʊdər/) are primitive operations upon linked lists composed of cons cells. A cons cell is composed of two pointers;… …88

**IBM 709**— The IBM 709 was an early computer system introduced by IBM in August, 1958. It was an improved version of the IBM 704 and the second member of the IBM 700/7000 series of scientific computers. The IBM 709 added overlapped input/output, indirect… …89

**IBM 700/7000 series**— The IBM 700/7000 series was a series of large scale (mainframe) computer systems made by IBM through the 1950s and early 1960s. The series included several different, incompatible processor architectures. The 700s used vacuum tube logic and were… …90

**Plus and minus signs**— This article is about the mathematical symbols. For other uses of plus , see Plus (disambiguation). For other uses of minus , see Minus (disambiguation). The plus and minus signs (+ and −) are mathematical symbols used to represent the notions of …