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In C and C++ arrays do not support the size function, so programmers often have to declare separate variable to hold the size, and pass it to procedures as a separate parameter. Elements of a newly created array may have undefined values (as in C), or may be defined to have a specific "default" value such as 0 or a null pointer (as in Java).
Many languages have explicit pointers or references. Reference types differ from these in that the entities they refer to are always accessed via references; for example, whereas in C++ it's possible to have either a std:: string and a std:: string *, where the former is a mutable string and the latter is an explicit pointer to a mutable string (unless it's a null pointer), in Java it is only ...
Many languages (e.g. Java, Pascal and Ada) implement Booleans adhering to the concept of Boolean as a distinct logical type. Some languages, though, may implicitly convert Booleans to numeric types at times to give extended semantics to Booleans and Boolean expressions or to achieve backwards compatibility with earlier versions of the language.
In addition to support for vectorized arithmetic and relational operations, these languages also vectorize common mathematical functions such as sine. For example, if x is an array, then y = sin (x) will result in an array y whose elements are sine of the corresponding elements of the array x. Vectorized index operations are also supported.
Each pointer has a type it points to, but one can freely cast between pointer types (but not between a function pointer and an object pointer). A special pointer type called the “void pointer” allows pointing to any (non-function) object, but is limited by the fact that it cannot be dereferenced directly (it shall be cast).
The reset() method causes the position pointer to move to the mark pointer's position. Upon invocation of the clear() method or the flip() method the mark pointer is discarded. The clear() method does not ensure zero-ing of the buffer, but does return the limit pointer to the upper boundary of the underlying array, and the position pointer to zero.
Arbitrary memory blocks may be allocated in Java as an array of bytes. Java and C++ use different idioms for resource management. Java relies mainly on garbage collection, which can reclaim memory, [7] while C++ relies mainly on the Resource Acquisition Is Initialization (RAII) idiom. This is reflected in several differences between the two ...
Multidimensional arrays can in some cases increase performance because of increased locality (as there is one pointer dereference instead of one for every dimension of the array, as it is the case for jagged arrays). However, since all array element access in a multidimensional array requires multiplication/shift between the two or more ...