Are arrays in C++ same as C?

Does the C++ compiler treat the arrays same way as in C?

E.g

In C,

• An array access using subscript operator is always interpre开发者_如何学Pythonted as a pointer.
• In function argument, array declarations are treated as pointer to start of element.

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Yes and no. Arrays work the same in both languages for the most part (C99 supports variable-length arrays, while C++ doesn't, and there may be a few other subtle differnces as well).

However, what you're saying isn't exactly true either. The compiler doesn't treat an array access as a pointer, not even in C. An array access can be more efficient in some cases, because the compiler has better information on aliasing available in the array case. In both C and C++, a plain pointer access means that the compiler has to assume that it may alias any other compatible type. If the compiler simply treated it as a pointer dereference, then this optimization opportunity would be lost.

Edit
As pointed out in a comment, the language standard does define array subscripting in terms of pointer arithmetics/dereferencing. Of course, actual compilers make use of the additional information that a pointer is really an array, so they're not treated exactly like pointers, but that could be considered an optimization beyond what the standard mandates.

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Not exactly same as in C99. C99 supports Variable Length Array (VLA), but C++ doesn't.

void f(int n)
{
   int array[n]; //valid C99, but invalid C++
}

That means, C++ compilers do not treat the arrays same way as do C (i.e C99) compilers.

However, other version of C (i.e C89) doesn't support VLA. So C89 arrays would be [almost] same as C++ arrays.

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Yes, they are treated in the same way. However, in C++ you probably should not be using them - investigate the std::vector class!

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Yes. Arrays are treated in the same way in C and C++. However, C++ now has the STL, which is a collection of data structures and operations on them, such as string, vector, deque etc.

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Yes, C++ is an extended version of C language apart from its interesting and appealing OOP features. Strostrupp and other designed it with sole intention of creating a Object Oriented Language with C like syntax. Fundamentally both are same in most cases (excluding C++'s OOP features) and arrays are not an exception.

"An array is basically a pointer to a sequential memory block. where the name of the array represents the first location of that block." This statement is true for both C and C++.

Array Implementation is same though there are some restrictions in how C++ compilers allow you to use them.