What is the Difference Between Array and Structure in C Programming

The main difference between Array and Structure in C programming is that the array helps to store a collection of data elements of the same type while the structure helps to store different data types as a single unit.

C is a high-level general purpose programming language developed by Dennis Ritchie at Bell Labs. It is the foundation language for most modern programming languages such as C++, Java, Python, and PHP. Operating systems, embedded systems, network drivers, databases, etc. are some applications we can develop using C language. Array and Structure are two essential programming concepts in C language. Overall, the elements in an array have the same data type whereas the elements in a structure have different data types.

Key Areas Covered

1. What is Array in C programming
     – Definition, Functionality
2. What is Structure in C programming
     – Definition, Functionality
3. What is the Difference Between Array and Structure in C programming
nofollow      – Comparison of Key Differences

Key Terms

Array, Structure, C, C++

What is Array in C Programming

An array is a data structure that is capable of storing elements that belong to the same data type. The programmer has to declare the number of elements the array should store. Therefore, an array has a fixed length. Consider the following as an example.

int numbers [10];

In this, the array cannot store more than 10 elements. The first element of the array starts with the zero index. The index of the last element is 9. Furthermore, all the elements are stored in the contiguous memory location. Therefore, the memory allocation of an array is static.

Figure 1: C program with arrays

Above is a simple program with C. The “marks” is an array. It can store five integer values. The programmer initializes the array with five marks. The ‘for loop’ helps to iterate through the array. The ‘i’ variable starts with 0 and increments till 4. It prints the marks in the array sequentially. The first element is 75 while the last element is 66.

What is Structure in C Programming

A structure is a single variable that can hold data that belongs to different data types. In other words, it is a set of variables with dissimilar data types. An example is as follows.

Figure 2: C program with structure

In the above program, student is a structure. It contains two properties: id (int ) and name (char). In the main method, s1 is a structure type variable. In line 13, number 1 is assigned to id property of the structure. The strcpy function allows copying the string “Ann” to the name property of the structure. The programmer can access the properties of the structure using the access operator (.). Finally, the printf function displays the id and name on the console.

Difference Between Array and Structure in C Programming

Definition

Array is a data structure consisting of a collection of elements each identified by the array index while structure is a data type that stores different data types in the same memory location. Thus, this is the main difference between Array and Structure in C programming.

Functionality

Array stores a set of data elements of the same data type in contiguous memory locations whereas structure stores different data types as a single unit.

Access

It is possible to access an array element using the index. However, it is possible to access a property of a structure using the structure name and the dot operator. Hence, this is another difference between Array and Structure in C programming.

Keyword

Furthermore, there is no keyword to declare an array, but the programmer uses the “struct” keyword to declare a structure.

Data Element Size

Another difference between Array and Structure in C programming is the size of data elements. Each element in an array has the same size while the size of the elements in a structure can be different.

Accessing and Searching Elements

Moreover, Structure requires more time to access and search elements when compared to an array.

Conclusion

Array and Structure are two important concepts in C programming. The programmer can directly declare an array whereas structure is a user-defined data type. The difference between Array and Structure in C programming is that the array helps to store a collection of elements of the same data type while the structure helps to store different data types as a single unit.

Reference:

1. “C Array – Javatpoint.” Www.javatpoint.com, Available here.
2. “Structure in C – Javatpoint.” Www.javatpoint.com, Available here.