What is a boolean value in C? What does it do, can you give a simple list?

bool is a boolean variable, that is, a determinant of a logical variable, similar to float, double, etc., except that float defines floating-point and double defines double-precision floating-point. Boolean variables have only true and false values. Examples:

#includeusing namespace std; int main()

It is true (true), false (false) two ways to represent the state, for example, whether the software starts automatically ****, you can set it to true or false to complete, of course, you can also use other strings like (yes) or (no) to complete, but the use of boolean value is more explicit, the effect is the same, using boolean value will limit the possibility to two, either true, or false, there will be no other possibilities!

It's true or not. For example, let your sun exist or not, either yes or no. The data for such results is stored in Boolean type.

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Upstairs just said the opposite, it won't go into the loop at all.

Bool is supposed to be defined only as true and false, but in C++, non-0 is true and 0 is false.

if(35)

The content of this if statement block will also be executed normally.

Two values, 0 and 1, with 0 representing false and 1 representing ture

while(0)

Indicates an endless loop...

bool means Boolean, and the return value of Boolean is only true and false, which is mostly used for judgment.

In C, there are two kinds of results, true and false, true and true: 0 is false, and non-0 is true. For example:

#include

intmain（）｛

inta，b，flag；

scanf("%d %d", &a, &b);

flag = a > b;flag holds the result of the relational operation printf( flag d n ,flag);

return0；Running Result:

flag＝0

C doesn't syntactically support "true" and "false" outright, just 0 and non-0. This is improved in C, which adds a bool type (boolean type), which typically takes up 1 byte in length. The bool type has only two values, true and false

true means "true" and false means "false".

In C, bool stands for Boolean variable.

Bool Boolean variables, also known as the determinants of logical variables, are named after George Boole, the British mathematician and founder of Boolean algebra. bool is similar to float, double, etc., except that float defines floating-point type, and double defines double-precision floating-point type.

Boolean variables have only true and false values. Boolean variables can be used in logical expressions, i.e., logical operations such as "or", "and", "not", and relationship operations such as greater than less than, where the result of the logical expression is true or false.

bool can be used to define the function type as boolean, and the function can have return true; return false.

bool is a boolean value, and it has only two values, one true and one false;

Or say that one is true and the other is false;

This means to shift left, >> this one is to move right;

If it is <<2, it means to shift 2 places to the left, 0111 1100 and 2 places to the left is 1111 0000

bool boolean. i.e. yes or no to determine the type. You know, int float double char, these are numeric values. Character type.

0 to false, non-0 to true

The class's overloaded function int operator bool() defines how the class is converted to a Boolean value.

Judge the truth from the fake. C99 has been added to make C++ more compatible.

#define false 1

#deifne ture 0

1. C++ can also be output in printf format. 2. It contains the iomanip header file, and COUT can also be output in format. Specifically: include

There are many roles of iomanip in this:

It is mainly used for some manipulation operators such as cin, cout, etc., such as setfill, setw, setbase, setprecision, etc. It's the IO flow control header file, just like the formatted output inside C. Here are some common control functions:

dec is set to a base of 10 which is equivalent to"%d"The hex base is 16 equivalent to"%x"

The oct base is 8 which is equivalent to"%o"Function: permanent sample: cout<<12setw(n) Set the field width to n characters The function is temporary.

The meaning of this controller is to ensure that the output width is n. Such as:

cout<1 10100 (right-aligned by default) When the output length is greater than 3 (<< 1000), setw(3) does not work. setfill(c) sets the padding character to c setioflags(ios::fixed) for a fixed floating-point display.

The SetIoFlags(ios::scientific) index represents the sample CoutSetIoFlags(ios::right) right aligned.

setiosflags(ios::skipws) ignores leading whitespace.

setiosflags(ios::uppercase) uppercase output of hexadecimal numbers.

setiosflags(ios::lowercase) 16decimal lowercase output.

setiosflags(ios::showpoint) forces the display of a decimal point.

setiosflags(ios::showpos) forces the display of the symbol sample: cout

C++ with iomainip library files, including output control formats such as precision.

Here's a description of some of the functions of that library.