Basic structure of a C program

The basic structure of a C program consists of several parts, which are as follows:

1. Preprocessor Directives: This section contains the preprocessor directives, which are instructions to the compiler to perform certain operations before the program is compiled. These directives begin with the symbol “#”. For example, #include is a preprocessor directive that tells the compiler to include the standard input/output library in the program.

2. Main Function: Every C program must have a main function, which is the starting point of the program. The main function is defined using the keyword “int” (which indicates the function returns an integer value) followed by the function name “main()”, and a pair of parentheses “()”. The main function contains the code that is executed when the program is run.

3. Declarations: This section contains declarations of variables and functions used in the program. Variables are declared using a data type, such as “int” or “float”, followed by a variable name. Functions are declared using their return type, function name, and arguments.

4. Statements: This section contains the statements that make up the program. Statements can include assignments, conditionals, loops, and function calls, among other things.

Here is an example of a simple C program that prints “Hello, World!” to the console:

#include 

int main() {
    printf("Hello, World!\n");
    return 0;
}

In this program, the “#include ” directive includes the standard input/output library, which contains the “printf” function. The main function contains a call to the “printf” function, which prints the string “Hello, World!” to the console. The “return 0” statement indicates that the program is completed successfully.