C++primer Note--chapter One

1. Data type

1) Basic data type: Int,char,float,double,bool

Eg:int a=1; Defines an int type object (variable) and initializes it to 1

2) Extended base data type: vector (vector), list, string (string), complex number (plural)

Eg: #include <vector> must have a header file

#include <string> must have a header file

Vector<string> Chapter_titles (20); Defines a vector object with 20 elements of a string type

2. Preprocessor Indicator

1) #include

1) shaped like <iosteam>: standard header file, search by default directory

2) shaped like "myfile.h": User-defined file, search under current directory

2) Condition Indicator: Prevents repeated processing when a header file is referenced by multiple files

Eg: #ifndef bookstore_h if not defined Bookstore.h

#define BOOKSTORE_H , then define Bookstore.h .

/* Contents of the Bookstore.h */ header file

End of #endif definition

PS: #ifndef =if not define #ifdef =if define Bookstore_h is a preprocessor constant of bookstore.h

3) Common Processor text

1) _cplusplus: According to it to determine whether the program is a C + + program

2) _stdc_: According to it to determine whether the program is a C + + program

3) _line_: The number of rows currently compiled to

4) _file_: The currently compiled file name

5) _time_: The current compile time

6) _date_: Date of the current compilation

7) Aseert (): Pre-processing macros. Execution continues when the preconditions in parentheses are met, otherwise an error message is displayed and terminated.

(C:assert.h C++:cassert)

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C++primer Note--chapter One