C++ Iterator Library - random_access_iterator_tag

Description

It used to identify the category of an iterator and a random-access iterator support at least one of the following operations.

property	valid expressions
It is a default-constructible, copy-constructible, copy-assignable and destructible	`X a;` `X b(a);` `b = a;`
It can be compared for equivalence using the equality/inequality operators (meaningful when both iterator values iterate over the same underlying sequence).	`a == b` `a != b`
It can be dereferenced as an rvalue (if in a dereferenceable state).	`*a` `a->m`
For mutable iterators (non-constant iterators): Can be dereferenced as an lvalue (if in a dereferenceable state).	`*a = t`
It can be incremented (if in a dereferenceable state). The result is either also dereferenceable or a past-the-end iterator. Two iterators that compare equal, keep comparing equal after being both increased.	`++a` `a++` `*a++`
It can be decremented (if a dereferenceable iterator value precedes it).	`--a` `a--` `*a--`
Supports the arithmetic operators `+` and `-` between an iterator and an integer value, or subtracting an iterator from another.	`a + n` `n + a a - n` `a - b`
Can be compared with inequality relational operators (`<`, `>`, `<=` and `>=`).	`a < b` `a > b a <= b` `a >= b`
Supports compound assignment operations `+=` and `-=`	`a += n` `a -= n`
Supports the offset dereference operator (`[]`)	`a[n]`

property	valid expressions
It is a default-constructible ,copy-constructible ,copy-assignable and destructible	`X a;` `X b(a);` `b = a;`
It can be compared for equivalence using the equality/inequality operators (meaningful when both iterator values iterate over the same underlying sequence).	`a == b` `a != b`
It can be dereferenced as an rvalue (if in a dereferenceable state).	`*a` `a->m`
For mutable iterators (non-constant iterators): Can be dereferenced as an lvalue (if in a dereferenceable state).	`*a = t`
It can be incremented (if in a dereferenceable state). The result is either also dereferenceable or a past-the-end iterator. Two iterators that compare equal, keep comparing equal after being both increased.	`++a` `a++` `*a++`
It can be decremented (if a dereferenceable iterator value precedes it).	`--a` `a--` `*a--`
It supports the arithmetic operators `+` and `-` between an iterator and an integer value, or subtracting an iterator from another.	`a + n` `n + a a - n` `a - b`
It can be compared with inequality relational operators (`<`, `>`, `<=` and `>=`).	`a < b` `a > b a <= b` `a >= b`
It supports compound assignment operations `+=` and `-=`	`a += n` `a -= n`
It supports the offset dereference operator (`[]`)	`a[n]`
Lvalues are swappable.	`swap(a,b)`

Following is the declaration for std::random_access_iterator_tag.

struct random_access_iterator_tag {};

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