So we've learnt how to collect basic data from the user, but wouldn't it be useful if we could do different things depending on what the user typed in? Well this happens to be a very core concept of computer programming, and we can do exactly as previously described with these things called 'if' statements. These are basic statements which allow us to do certain things only in certain conditions.
The first thing we're going to learn about is the 'if' itself. Just write the
if keyword and then in some brackets, the condition. To specify the condition you simply write one value (either a variable or constant), then the comparison operator you want to compare them with (for example - equal to, which is ) and then the second value (either a variable or constant). We then put some curly brackets, and anything inside the curly brackets is what will be executed if the condition is true. For example, the following would compare 1 to 1 (which is a bit silly, but gives an example which is obviously always true):
Note that the value that you are comparing the second thing to must match the type of the first thing - for example, if comparing a string you must either compare to a string variable, or to a string constant (and remember that string constants are always shown in double quotes). In our example, however, one always equals one, so it's not much of a condition -- we can use variables to actually create a somewhat useful condition:
In this case the program would output 'Wow, I'm 16 too!' if the user entered the value 16, but would not output anything if the user inputted any other number. We can also compare any two variables using the same method:
Auto tune rap app for android iphone. The export keyword is intended to allow definitions of C templates to be separated from their declarations. While officially part of the C standard, the export keyword is only supported by a few compilers (such as the Comeau C compiler) and is not supported by such mainstream compilers as GCC and Visual C. Summary of basic C-commands Compiling To compile a C-program, you can use either gor c. G -oexecutable filename.out sourcefilename.cc c -oexecutable filename.out sourcefilename.cc e.g. G -o Csampleinout.out Csampleinout.cc For the following commands you can find at the end of this summary sample programs. Each command in C is followed by “;”. Keywords double and float are used for declaring floating type variables. For example: float number; double longNumber; Here, number is a single-precision floating type variable whereas, longNumber is a double-precision floating type variable. To learn more, visit C data types.
The issue we have at the moment, is that in most programs we aren't always going to want to just check if something is equal to something else. What if we wanted to check if something was less than, or greater than, or not equal to something else? Well luckily there are other comparison operators we can use instead of just being restricted to the 'is equal to' operator (). 'Less Than' (
< ) and 'Greater Than' (> ) are relatively simple - they are simply their usual symbols, and so we could check if the user's height is greater than their age like this:
Different Keywords And Commands In Dev C Download
We can also do 'Greater Than or Equal To' and 'Less Than or Equal To' by simply adding a single equals sign after the appropriate symbol. For example, we could check if the user's height was less than or equal to their age like this:
There are also the simple 'equal to' and 'not equal to' conditional operators. We already know 'equal to' as , and 'not equal to' is an exclamation mark followed by an equals sign:
!= . So we could check if the user's height doesn't equal their age like so:
Ok, so now that we can compare two values pretty well - what if we want to do a variety of things depending on different conditions? For example if we wanted to do one thing if their height and age were equal, and if they aren't then do something else if another condition is met. Well we can accomplish this using 'else if'. You can just write
else if after your closing curly bracket for your original 'if' statement, and then specify your 'else if' condition followed by the curly brackets to contain the code to be executed if they are met. For example:
Analog pro vst crack. Notice that it's very easy just to string together 'if's and 'else if's, in this case I've just chained two 'else if's off my original 'if'. We can also specify something to do if none of the conditions are met (in our example above this wouldn't really be useful since it's impossible not to meet any of the conditions, but it's generally good practice to put an else in just in case something goes seriously wrong). We can do this using the
else keyword, and then some curly brackets to specify the code that could be executed at the end of our 'daisy chain':
![]()
A great example of 'daisy chaining' these all up is to create a program which asks for a student's test score, and then spits out the grade that they got. Try and create such an application yourself and see how you do. One solution to the problem is as follows, however it's worth noting that repeating this much code should be making your 'bad code' sense tingle! It goes against the 'Don't Repeat Yourself' principle of programming, but for now, a solution like this will have to do:
< cpp
C++
C++ Keyword Using
This is a list of reserved keywords in C++. Since they are used by the language, these keywords are not available for re-definition or overloading.
Note that
and , bitor , or , xor , compl , bitand , and_eq , or_eq , xor_eq , not , and not_eq (along with the digraphs <% , %> , <: , :> , %: , and %:%: ) provide an alternative way to represent standard tokens.
In addition to keywords, there are identifiers with special meaning, which may be used as names of objects or functions, but have special meaning in certain contexts.
![]()
Also, all identifiers that contain a double underscore __ in any position and each identifier that begins with an underscore followed by an uppercase letter is always reserved and all identifiers that begin with an underscore are reserved for use as names in the global namespace. Auto tuning samsung tv greyed out. See identifiers for more details.
The namespace
std is used to place names of the standard C++ library. See Extending namespace std for the rules about adding names to it.
C++ Keywords Download
The following tokens are recognized by the preprocessor when in context of a preprocessor directive:
The following tokens are recognized by the preprocessoroutside the context of a preprocessor directive:
Different Keywords And Commands In Dev C File
Keyword Search Key Command[edit]See alsoDifferent Keywords And Commands In Dev C Language
Retrieved from 'https://en.cppreference.com/mwiki/index.php?title=cpp/keyword&oldid=114173'
Comments are closed.
|
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |