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C++ How to use functions

A function is a group of statements that together perform a task. Every C++ program has at least one function, which is main() , and all the most trivial programs can define additional functions. You can divide up your code into separate functions. How you divide up your code among different functions is up to you, but logically the division usually is so each function performs a specific task. A function declaration tells the compiler about a function's name, return type, and parameters. A function definition provides the actual body of the function. The C++ standard library provides numerous built-in functions that your program can call. For example, function strcat() to concatenate two strings, function memcpy() to copy one memory location to another location and many more functions. A function is knows as with various names like a method or a sub-routine or a procedure etc. Defining a Function: The general form of a C++ function definition is as follows: re...

C++ Decision Making

Decision making structures require that the programmer specify one or more conditions to be evaluated or tested by the program, along with a statement or statements to be executed if the condition is determined to be true, and optionally, other statements to be executed if the condition is determined to be false. Following is the general from of a typical decision making structure found in most of the programming languages: C++ programming language provides following types of decision making statements. Click the following links to check their detail. Statement Description if statement An if statement consists of a boolean expression followed by one or more statements. if...else statement An if statement can be followed by an optional else statement, which executes when the boolean expression is false. switch statement A switch statement allows a variable to be tested for equality against a list of values. nested if statements You can use one if or else if statement ...

C++ Loop Types

There may be a situation, when you need to execute a block of code several number of times. In general statements are executed sequentially: The first statement in a function is executed first, followed by the second, and so on. Programming languages provide various control structures that allow for more complicated execution paths. A loop statement allows us to execute a statement or group of statements multiple times and following is the general from of a loop statement in most of the programming languages: C++ programming language provides the following types of loop to handle looping requirements. Loop Type Description while loop Repeats a statement or group of statements while a given condition is true. It tests the condition before executing the loop body. for loop Execute a sequence of statements multiple times and abbreviates the code that manages the loop variable. do...while loop Like a while statement, except that it tests the condition at the end of ...

C++ How to use operators

An operator is a symbol that tells the compiler to perform specific mathematical or logical manipulations. C++ is rich in built-in operators and provides the following types of operators: Arithmetic Operators Relational Operators Logical Operators Bitwise Operators Assignment Operators Misc Operators This chapter will examine the arithmetic, relational, logical, bitwise, assignment and other operators one by one. Arithmetic Operators: There are following arithmetic operators supported by C++ language: Assume variable A holds 10 and variable B holds 20, then: Operator Description Example + Adds two operands A + B will give 30 - Subtracts second operand from the first A - B will give -10 * Multiplies both operands A * B will give 200 / Divides numerator by de-numerator B / A will give 2 % Modulus Operator and remainder of after an integer division B % A will give 0 ++ Increment operator, increases integer value by one A++ will give 11 -- Decrement ope...

C++ How to Storage Classes

A storage class defines the scope (visibility) and life-time of variables and/or functions within a C++ Program. These specifiers precede the type that they modify. There are following storage classes, which can be used in a C++ Program auto register static extern mutable The auto Storage Class The auto storage class is the default storage class for all local variables. { int mount ; auto int month ; } The example above defines two variables with the same storage class, auto can only be used within functions, i.e., local variables. The register Storage Class The register storage class is used to define local variables that should be stored in a register instead of RAM. This means that the variable has a maximum size equal to the register size (usually one word) and can't have the unary '&' operator applied to it (as it does not have a memory location). { register int miles ; } The register should only be used for variab...

C++ Modifier Types

C++ allows the char, int, and double data types to have modifiers preceding them. A modifier is used to alter the meaning of the base type so that it more precisely fits the needs of various situations. The data type modifiers are listed here: signed unsigned long short The modifiers signed, unsigned, long, and short can be applied to integer base types. In addition, signed and unsigned can be applied to char, and long can be applied to double. The modifiers signed and unsigned can also be used as prefix to long or short modifiers. For example, unsigned long int . C++ allows a shorthand notation for declaring unsigned, short, or long integers. You can simply use the word unsigned, short, or long , without the int. The int is implied. For example, the following two statements both declare unsigned integer variables. unsigned x ; unsigned int y ; To understand the difference between the way that signed and unsigned integer modifiers are interpreted ...

C++ Constants/Literals

Constants refer to fixed values that the program may not alter and they are called literals . Constants can be of any of the basic data types and can be divided into Integer Numerals, Floating-Point Numerals, Characters, Strings and Boolean Values. Again, constants are treated just like regular variables except that their values cannot be modified after their definition. Integer literals: An integer literal can be a decimal, octal, or hexadecimal constant. A prefix specifies the base or radix: 0x or 0X for hexadecimal, 0 for octal, and nothing for decimal. An integer literal can also have a suffix that is a combination of U and L, for unsigned and long, respectively. The suffix can be uppercase or lowercase and can be in any order. Here are some examples of integer literals: 212 // Legal 215u // Legal 0xFeeL // Legal 078 // Illegal: 8 is not an octal digit 032UU // Illegal: cannot repeat a suffix Following are other exampl...