Can a static array have a variable size?

You cannot declare a static array of variable size because its space is allocated in the Data Segment (or bss segment in case of an uninitialized variable). Hence the compiler needs to know the size at the compile time and will complain if the size is not a constant.

Is array size fixed in C?

Arrays a kind of data structure that can store a fixed-size sequential collection of elements of the same type. An array is used to store a collection of data, but it is often more useful to think of an array as a collection of variables of the same type.

What is a variable length array in C?

In computer programming, a variable-length array (VLA), also called variable-sized or runtime-sized, is an array data structure whose length is determined at run time (instead of at compile time). In C, the VLA is said to have a variably modified type that depends on a value (see Dependent type).

Why are variable length arrays bad?

The biggest problem is that one can not even check for failure as they could with the slightly more verbose malloc’d memory. Assumptions in the size of an array could be broken two years after writing perfectly legal C using VLAs, leading to possibly very difficult to find issues in the code.

What is the difference between static array and dynamic array in C?

Static arrays are allocated memory at compile time and the memory is allocated on the stack. Whereas, the dynamic arrays are allocated memory at the runtime and the memory is allocated from heap.

Can array be declared without a specified size?

Answer: No. It is not possible to declare an array without specifying the size. If at all you want to do that, then you can use ArrayList which is dynamic in nature.

Do arrays have a fixed size?

An array is a container object that holds a fixed number of values of a single type. The length of an array is established when the array is created. After creation, its length is fixed.

What is the size of array in C?

To determine the size of your array in bytes, you can use the sizeof operator: int a[17]; size_t n = sizeof(a); On my computer, ints are 4 bytes long, so n is 68. To determine the number of elements in the array, we can divide the total size of the array by the size of the array element.

How is a variable length array defined?

A variable length array can be used in a typedef statement. The typedef name will have only block scope. The length of the array is fixed when the typedef name is defined, not each time it is used. A function parameter can be a variable length array.

Are variable length arrays bad C?

Safe and useful variable length arrays It’s safe because there’s no arbitrary stack allocation. Pointers to arrays are a rare sight in C code, whether variable length or not.

Is VLA safe?

You are right that VLA’s are basically always unsafe. The only exception is if you ensure that you never make them larger than a size you would feel safe making a fixed-size array, and in that case you might as well just use a fixed-size array.