C++ Programming Code Examples
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There are different preprocessor directives that perform different tasks.
/* There are different preprocessor directives that perform different tasks.
There are different preprocessor directives that perform different tasks. You can categorize these Preprocessor Directives as follows: */
Inclusion Directives:
#include: specifies the files to be included, especially header-files
Macro Definition Directives:
#define: define a macro substitution
#undef: It is used for undefining a macro
Conditional Compilation Directives:
#if: It tests a compile-time condition
#elif
#endif: It specifies the end of #if
#ifdef: It is used to test for macro definition
#ifndef: It tests whether a macro is not defined
#else: It provides an alternative option when #if fails
Other Directives:
#error
#line: Supplies a line number for compiler messages
#pragma: It specifies implementation-defined instructions to the compiler
The #ifndef directive of the C++ Programming Language helps in allowing the conditional compilation. The C++ Programming Language's preprocessor helps in determining only if the macro provided is not at all existed before including the specific subsequent code in the C++ compilation process. The #ifndef preprocessor only checks If the specific macro is not at all defined with the help of the #define directive. If the condition is TRUE then it will be helpful in executing the code otherwise the else code of the #ifndef will be compiled or executed only if present.
In the C++ Programming Language, the #define directive allows the definition of macros within your source code. These macro definitions allow constant values to be declared for use throughout your code. Macro definitions are not variables and cannot be changed by your program code like variables. You generally use this syntax when creating constants that represent numbers, strings or expressions. The syntax for creating a constant using #define in the C++ is: #define token value
#include is a way of including a standard or user-defined file in the program and is mostly written at the beginning of any C/C++ program. This directive is read by the preprocessor and orders it to insert the content of a user-defined or system header file into the following program. These files are mainly imported from an outside source into the current program. The process of importing such files that might be system-defined or user-defined is known as File Inclusion. This type of preprocessor directive tells the compiler to include a file in the source code program.
The C++ comments are statements that are not executed by the compiler. The comments in C++ programming can be used to provide explanation of the code, variable, method or class. If we write comments on our code, it will be easier for us to understand the code in the future. Also, it will be easier for your fellow developers to understand the code. By the help of comments, you can hide the program code also. There are two types of comments in C++: • Single Line comment. • Multi Line comment
Finding the transitive closure using Warshall's Algorithm. The Transitive Closure of a binary relation R on a set X is the 'transitive relation' R+ on set X such that R+ contains R and R+ is
