Assignment, relations, logical operators

cout << boolalpha into the printout 0 false, 1 into true

 

Logical Operators:

&& (AND) and two conditions are true when the result is true

|| (or), or when two conditions are true is true  

! Non-inverted

 

Bit operators (binary):

& Bitwise compared with the same 1 1

| Bitwise or there was a 1 1

~ Bitwise inverted (negated 8), is converted into a negative binary 10 hex: binary negated, + 1, then take a negative

^ Bitwise XOR 0 is the same; different 1

<< 0 cases left right gap fill: 2 << 3 10 binary ----> 10000 16-bit result

>> shift right sign bits fill the vacancy left

 

sizeof operator used to obtain the size of the memory space occupied by the data type

Usage: sizeof (type_name)

Results bits in byte units

 

 

Operator precedence:

 

 Three operators:

int num = 5> 6? 10: 12;

5 is greater than 6, otherwise it returns 10 12 

 

 

if the structure: 

if (true)
 {

 }
 else
 {

 }

 Example:

// use the program to determine whether the character entered by the user is legitimate hard disk drive 
    char PAN = ' \ 0 ' ;   // default value is set to null character 
    cout << " Please enter a character, I judge the legality of \ the n- " ; 
    CIN >> PAN;
     // 'A' ~ 'the Z' 
    IF (PAN> = ' A ' && PAN <= ' the Z ' ) // 'A' may also be a 65 (ascii code) 
    { 
        COUT << " legitimate letter " << endl;
    } 
    The else 
    { 
        COUT << " illegal letter" << endl;
    }
    
    system("pause");

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

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