Macro-instruction which is popularly known as macro refers to a pattern that provides basic sequence of the input (different types of characters) and is mapped to replace the output sequence. This mapping is done with the help of specified characters that are called macro expansion. With macros the tasks involved in programming languages becomes less repetitive and thus enables the programmer to just reuse the code and get their work done.
When programmers use macros then they have a sequence of instructions available with them, this means that it makes their task simple and prone to little or no errors. This is the reason why macros are recognized to be the big block of coding, and if you are programmer who frequently participates at different programming contents then you cannot afford to miss macros in your list.
Macros can give you speed, precision and clarity which are quintessential for contests; this is why here are some of the common macros that any programmer should never forget to use.
1. #include <bits/stdc++.h>
This is one of the most common forms of macros that are used by programmers for various contents. Though this macro they can have accesses to standard library without having to type an entire command. The standard library can give them accesses to
B. Re-written codes
C. Data centers or
D. Associated help that is required for programming.
It is a great macro that people have been using for years, and till today they have nothing to complain about it, and that is what makes it an absolute success.
2. #define pb push_back
Push back stream with macro text â€œ#define pb push_backâ€ is a district tool that helps the programmer to push-back the bytes or characters that are unread. This macro is basically used for breaking large inputs into smaller and readable fragments.
For example, when dealing with lexical scanner the programmer knows that fragment or token (the identifier) ends only when the first character is read, having seen that the programmer pushes it back so that they can proceed with the next token.
3. #define cpresent(c, x) (find (all(c), x)! = (c).end ())
This is a debugging macro that is commonly used as a complier for various programming languages. One can find this macro at the checklist of any programmer. The ease of use and flexibility that this macro brings helps the programmer to complete their work with perfection.
It is a user friendly macro that even beginners have in their mind, when they take part in ground level contents, so as to give their career a perfect boost.
4. #include <fstream>
This belongs to the class of generic templates that is implemented for input/output file operations. Basically, this macro is always used along with an alias that works on the type of character along with a default operation set of characters.
The use #include <fstream> is primarily done for implementations and abstractions. The interface that is supported by this is good enough to facilitate any form of stream and thus is regarded as one of the highest classes of efficient codes that can be a must have for any programmer.
For example, with the use of this macro the programmer does not depended upon the location of the data and thus can utilize it as memory buffer, data extraction tool and a web socket too without the need of recompilation.
5. #include <algorithm>
#include <algorithm> macro can be used for a variety of purposes. In fact, it defines endless collection of functions that are designed for a range of elements. Here, range denotes a sequence of characters or bytes that can be only accessed through pointers and iterators. Majority of them are part of the STL containers. Important thing that should be noted here is that algorithms need iterators so as to operate in an efficient manner. They work directly on its values but this does not affect the structure or size of the container in any possible way.
6. #define sz (a) int ((a).size ())
7. #include <iostream>
#include <fstream> macro is basically derived from #include <iostream>. It is often used for special language support and was invented by Bell Labs. The use of this macro is associated with C++ programming language, as it is known to be the ultimate platform to use macros.
It brings a unique approach to your coding techniques and makes your work easier with no technical flaws.
8. #include <cassert>
This is a one of kind macro that is use to capture programming errors. With #include <cassert> the programmers can understand the errors that have been taken place in the coding in no time.
The use of this macro is based on library implementation, where it holds the expression of which assert failed to deliver the desired results. In addition to that it even provides the source file, line number and even the place where the programming error took place. However, thing is that this macro can only detect the errors that are made by the program and not by the real-time user.
9. typedef pair<int, int> ii
When you are facing complications with pair of containers then typedef can come for your rescue. Though the macro â€œtypedef pair<int, int> iiâ€ you can transform the most complex aspect of the programming into a simple and understandable one. This macro can only be used for C & C++ programming languages. And they are commonly used in contests to stay away from potentially confusing, cumbersome aspects of the program.
10. typedef vector<vi> vvi;
This is another variant of typedef that is again best for C and C++ programming languages. It simplifies innumerable sections of codes and is used to indicate precise values in no time. â€œtypedef vector<vi> vviâ€ has become a phenomenal macro because of the convenience and ease that it could offer programmers during various contests.