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(Unions)

.

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union ManyMembers

{

char c;

short s;

int i;

float f;

double d;

};

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union MyUnion{

int i;

void* p;

};

MyUnion uni;

cout

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(Enumerations)

enum JOB_KINDS { JOB_DWARF, JOB_WARRIOR, JOB_SORCERER };

struct Character

{

JOB_KINDS jobType;

// .

};

Character c;

// c .

// c if (JOB_SORCERER== c.jobType)

{

// .

}

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0 .

, .

enum { JOB_DWARD, JOB_WARRIOR, JOB_SORCERER };

enum { JOB_DWARD = 0, JOB_WARRIOR = 1, JOB_SORCERER = 2};

=

enum { JOB_DWARD, JOB_WARRIOR = 3, JOB_SORCERER };

enum { JOB_DWARD, JOB_WARRIOR = 3, JOB_SORCERER = 4};

=

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.

.

.

.

enum Color { RED, BLUE, GREEN, SKYBLUE, MAGENTA, YELLOW };

Color color1 = RED;

color1 = SKYBLUE + YELLOW; // Error

Color1 += 3; // Error

Color color2;color2 = 5; // Error

int n = MAGENTA; // n 4 .int m = BLUE + 2; //m 3 .

Color color3 = (Color)2 // color3 GREEN .Color color4 = (Color)5000 // .

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(References)

int target = 20;

// .

int& ref = target;

cout

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.

// .

float a = 100.0f;

float b = 12.34f;

// r a . ( )float& r = a;

// r 200.0f . ( )r = 200.0f;

// r b 12.34f . ( )r = b;

// r 56.7f . ( )r = 56.7f

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Const

Const .

Const .

const int& rci = 100; // OKint& ci = 100; // Error

char c = A;

const int& rci = c; // OK

int& ci = c; // Error

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typedef

typedef

typedef unsigned char* uc_ptr;

unsigned char uc = A;

uc_ptr p = &uc;

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(Bit Fields)

struct Flags

{

int a : 3;

int b : 4;

int : 5; // 5 .bool c : 1;

};

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struct A

{

int i;

float f;

};

struct B

{

char c;Aa;

};

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(= )

, .

int arr[10][5];

// 10 .for ( int i = 0; i < 10; ++i )

{

for ( int j = 0; j < 5; ++j )

arr[i][j] = 10;

}

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char c = 1;

char* pc = &c;

char** ppc = &pc;

if ( *ppc == pc )

{

// .}

if ( **ppc == c )

{

// .

}

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