The declaration and initialization declares a pointer array and make it point to a constant array of 31 characters. The declaration and initialization declares an array of characters, containing 31 characters. And yes, the size of the arrays is 31, as it includes the terminating ‘\0’ character. Laid out in memory, it will be something like this for the … Read more
This is a char: It can only hold one character! This is a C-string: It can hold multiple characters. Another way to write the above is: The 0 at the end is called the NUL terminator. It denotes the end of a C-string. A char* stores the starting memory location of a C-string.1 For example, … Read more
Reviewing the basic terminology It’s usually good enough – unless you’re programming assembly – to envisage a pointer containing a numeric memory address, with 1 referring to the second byte in the process’s memory, 2 the third, 3 the fourth and so on…. What happened to 0 and the first byte? Well, we’ll get to … Read more
UPDATE This answer is rather old, and so describes what was ‘good’ at the time, which was smart pointers provided by the Boost library. Since C++11, the standard library has provided sufficient smart pointers types, and so you should favour the use of std::unique_ptr, std::shared_ptr and std::weak_ptr. There was also std::auto_ptr. It was very much … Read more
static_cast `static_cast` is used for cases where you basically want to reverse an implicit conversion, with a few restrictions and additions. `static_cast` performs no runtime checks. This should be used if you know that you refer to an object of a specific type, and thus a check would be unnecessary. Example: In this example, you … Read more
Reviewing the basic terminology It’s usually good enough – unless you’re programming assembly – to envisage a pointer containing a numeric memory address, with 1 referring to the second byte in the process’s memory, 2 the third, 3 the fourth and so on…. What happened to 0 and the first byte? Well, we’ll get to … Read more
First, the binky video may help. It’s a nice video about pointers. For arithmetic, here is an example: (Note that incrementing a pointer that contains a null pointer value strictly is undefined behavior. We used NULL because we were only interested in the value of the pointer. Normally, only use increment/decrement when pointing to elements … Read more
In this case, your array variable arr can actually also be treated as a pointer to the beginning of your array’s block in memory, by an implicit conversion. This syntax that you’re using: Is kind of just syntactic sugar. You could really replace it with this and it would still work: So in the same … Read more
foo->bar is equivalent to (*foo).bar, i.e. it gets the member called bar from the struct that foo points to.
When you have an assignment operator in a statement, the LHS of the operator must be something the language calls an lvalue. If the LHS of the operator does not evaluate to an lvalue, the value from the RHS cannot be assigned to the LHS. You cannot use: since 10 does not evaluate to an lvalue. You can use: since i does … Read more