1

C

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2009

2

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/. C. C. ., .

Linux, KDEEmacs. Linux . C.

,printf()scanf(),.C ifelse,switch,while,fordowhile.

VV . V .

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4

5

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Linux.

1.1 (OperatingSystem)

(/):(Hardware)(Software).,/,/.

(Operating System) (Hardware)/.:

(Interface). (resources)

(ResourceAllocation).:

/. . (Central Process Unit)

. (RAM)

, () ().

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1.2 Linux

UNIX , .1970..

6

UNIX /. IBMAIX,SUNSolaris,DECUltrix.

Linux (Open Source) UNIX .LinusTorvalds Linux 1991, . LinusLinuxInternet,.Linux Internet. Linux,.ScientificLinux.

1.3 Linux

To Linux , :

(,multitasking). To Linux .

(multiuser).Linux.

. Linux ( Pentium), 16 , .

(Portability)..Linux , .Linux (CPU), Intel x86, SPARC,Alpha,PowerPC,MIPS m68k.

(utilities).Linux.:

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.Linux,Windows,OS/2,UNIX.

1.3 Linux

Linux . (kernel).. , ,..,, . C, 1000 (Assembly).

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Linux.:

Bourne Again bash . Linux.

CcshBourne.

Korn ksh UNIX. Bourne.

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XWindows UNIX. . X, .X , . Linux XWindows, . TCP/IP, LinuxXWindows.

XWindows,MIT,.XWindows Linux XFree86. XFree86 X, X, ,.

XLinux.X xterm, X.

K Desktop Environment ( K KDE) Open Source , , UNIX Linux. KDE XWindows. , 1996, . , Qt, C++.KDE ( ) WindowsXP2000.

9

KDE GNOME .GNOMEKDE.KDE.

1.4 LinuxKDE.

/PC.WINDOWSLinux.(poweron).ScientificLinux.

Linux. :Login:Password.

. Login Password(userid)(password).Go!KDE(1.1).

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10

KDE., .(panel). , . (1.2):

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(StartApplication) (1 ). KDE..

(Shell Terminal emulationwindow) (2 ). Linux.

Konqueror : Web (Konqueror Web Browser) (3)..

FireFox : Web (FireFoxWebBrowser) (4). .

Email (5 ). .

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,.

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14

1.6 Linux. /home../home.student1,student2,student3.student1/home/student1.

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1.6 Linux.

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pwd:pwd.

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..: cdc_directory cd/usr/bin cd..

15

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mkdirdirname:dirname...mkdirnew_catalogrmdir dirname : dirname. : dirname . ...rmdirnew_catalogls : . ls :

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16

read().

write().

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chmod w filename : w(ho) = u (user), g(group), o(other), + : , - : . : r(read), w(write), x(execute).

.

cpfilename1filename2: filename1 filename2...cptest1.cnew_test1.crmfilename:filename.

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man onlineLinux.

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1.7 Emacs.

UNIX.

17

UNIX. Linux. .

, vi Emacs. Emacs...

C, test1.c. KDE:

emacstest1.c&

1.8. .&()..

Emacs Emacs.Emacs.

FileSave(CurrentBuffer)1.9.EmacsFileExitEmacs.

18

1.8:Emacs.

1.9:Emacs.

19

I:

C.

2.1 C.

C 70DennisRitchieAT&TBellLabs.ANSI(AmericanNationalStandardsInstitute)ANSIC.:

:. :. :

. (compiler) . /. C /.

2.2 C.

:

emacsexample1.c&

Emacs example1.c. (2.1):

FileSave(CurrentBuffer)(1.9).(compilation).:

gccexample1.c

a.out. , , .Enter.2.2:

20

2.1:C.

2.2:.

.

2.3 C.

2.1 :

.:/*ThisismyfirstCprogram*/

21

,/* */. C, /* */ . C .

#include.:

#include

#,include.include ( )/usr/includestdio.h. include stdio.h.

#include, stdio.h, ..stdio.h,math.h, stdlib.h, string.h . .

main()C.main(). main(int)(void)..

printf(). \n . printf() stdio.h.#include.

return.C.

main .

22

2.4 (compiler).

LinuxC,ccgcc.ccgccGNU (Free Software Foundation). gcc Linux.

gccexample1.c

a.out. ,.ex1:

gccoex1example1.c

ex1a.out.

. C, ..c.

gcc,,:

. /usr/include.

(objectfile)..o..:.

linker (

) . , ANSIC ,. , .(executablefile).

.ANSIC.

:

23

gcccfilename.c:filename.o.

filename.cmain.c.main.cfilename.o.:

gccopgmmain.cfilemane.o:pgm.

2.5 C.

,,,.

. . , :

a=1.35;b=32;

a=7.5; b=10;

ab1.3532 . ,.main,return,for.(,;?).

,

. . 100 3.1415 k,u.

C:

+

* / %

.7%52.

2.6

a=10;b=5;c=(a+

(a+5)*b

c=(a+

2.3

2.3:

.

:

;

+5)*b;

b

+5)*b;

.c.

.

3

75

.

.

.

24

,

.

. .

,

c

.

,.

75

.

(a+

C

.

,

5.

+5)*b

.

C

25

:int.int . int 32bit (4byte).2147483647(2311)2147483648.: inta,b; a=5;

b=7;

:doublefloat.doublefloat().float32bit(4byte)double64bit(8byte).float 1.4x1045 3.4x1038 7 . double4.9x103241.8x10308 15 . . . double, . double.: doublex;

floaty; x=3.14159;

y=7.;!y7, 7 .

: char. char . PC 256 . (AZaz),(09),.8bit(1byte).8bit,0(201)255(281)ASCII (AmericanStandardCode for Information Interchange). A, 65 ( 0x41), a 97 ( 0x61). 2.1 ASCII 128.

26

:void.(main(void)).

(qualifiers).:

shortlongint.:

shortintlongint

O short int 16 bit (2 byte) long int 32 bit (4 byte). longdouble.

longdouble

80bit (10byte) .

unsignedsigned int.unsignedsigned.:

unsignedinta;signedintb;

:unsignedshortinte;signedlongintf;

2.2.

2.1ASCII128.

Non-Printing Characters Printing Characters Name Control Dec Hex Char Dec Hex Char Dec Hex Char Dec Hex Char

null ctrl-@ 0 00 NUL 32 20 Space 64 40 @ 96 60 `start header ctrl-A 1 01 SOH 33 21 ! 65 41 A 97 61 astart of text ctrl-B 2 02 STX 34 22 " 66 42 B 98 62 bend of text ctrl-C 3 03 ETX 35 23 # 67 43 C 99 63 cend of xmit ctrl-D 4 04 EOT 36 24 $ 68 44 D 100 64 denquiry ctrl-E 5 05 ENQ 37 25 % 69 45 E 101 65 eacknowledge ctrl-F 6 06 ACK 38 26 & 70 46 F 102 66 fbell ctrl-G 7 07 BEL 39 27 ' 71 47 G 103 67 g

27

backspace ctrl-H 8 08 BS 40 28 ( 72 48 H 104 68 hhorizontal tab ctrl-I 9 09 HT 41 29 ) 73 49 I 105 69 iline feed ctrl-J 10 0A LF 42 2A * 74 4A J 106 6A jvertical tab ctrl-K 11 0B VT 43 2B + 75 4B K 107 6B kform feed ctrl-L 12 0C FF 44 2C , 76 4C L 108 6C lcarriage feed ctrl-M 13 0D CR 45 2D - 77 4D M 109 6D mshift out ctrl-N 14 0E SO 46 2E . 78 4E N 110 6E nshift in ctrl-O 15 0F SI 47 2F / 79 4F O 111 6F o

data line escape ctrl-P 16 10 DLE 48 30 0 80 50 P 112 70 pdev.cntrl.1 ctrl-Q 17 11 DC1 49 31 1 81 51 Q 113 71 qdev.cntrl.2 ctrl-R 18 12 DC2 50 32 2 82 52 R 114 72 rdev.cntrl.3 ctrl-S 19 13 DC3 51 33 3 83 53 S 115 73 sdev.cntrl.4 ctrl-T 20 14 DC4 52 34 4 84 54 T 116 74 tneg acknowledge ctrl-U 21 15 NAK 53 35 5 85 55 U 117 75 usync.idel ctrl-V 22 16 SYN 54 36 6 86 56 V 118 76 vend of xmit block ctrl-W 23 17 ETB 55 37 7 87 57 W 119 77 w

cancel ctrl-X 24 18 CAN 56 38 8 88 58 X 120 78 xend of medium ctrl-Y 25 19 EM 57 39 9 89 59 Y 121 79 ysubstitute ctrl-Z 26 1A SUB 58 3A : 90 5A Z 122 7A zescape ctrl-[ 27 1B ESC 59 3B ; 91 5B [ 123 7B {file separator ctrl-\ 28 1C FS 60 3C < 92 5C \ 124 7C |group separator ctrl-] 29 1D GS 61 3D = 93 5D ] 125 7D }record separator ctrl-^ 30 1E RS 62 3E > 94 5E ^ 126 7E ~unit separator ctrl-_ 31 1F US 63 3F ? 95 5F _ 127 7F DEL

2.2..

bits char 8 int 32 21474836482147483647shortint 16 3276832767longint 32 intfloat 32 1.4x10453.4x1038double 64 4.9x103241.8x10308

28

2.7 .

, . .

. main

intmain(void){.

..

C #include. . (globalvariables)..

. (.0)( ). . ,.

,,.

int. double float. double.

for.

.:

inta,b;doublex;a=5;

29

b=10;x=a/b;

x=0x=0.5.a/b.

double float () (.). o :

doublex,y; doublex,y;x=4; x=4.;y=9; y=9.;z=x*y; z=x*y;

,.:

doublex,y,z; x=2.; y=10.; z=(1/2)*x*y;

z=0 (1/2) 0.:

doublex,y,z; x=2.; y=10.; z=(1./2.)*x*y;

z=10.

2.8 (casting).

. . double float int ( 2 ). doublefloat.:

a2.inta;doublex; x=2.7; a=(int)x;

30

a.inta;doublex; x=1.234e24; a=(int)x;

x25.inta; inta;doublex; floatx; a=25; a=25;x=(double)a; x=(float)a;

.(casting).

C . . .(double)..

C . :

longdoubledoublefloatintshortint

2.9 printf().

printf() ,stdio.h.

2.3 printf(). :

Thenumber15isaninteger.

, .%.2.3

31

printf(Thenumber:%disaninteger.\n,15);

2.4printf().

2.3printf().

d,i int.o int..x,X int..u unsignedint.c char..s char..f float,double.e,E float,double..g,G float,double.

.

\n . \n.%%%.p. 2.5 , .2.3.

ThThThThThTh

.

2.5

heargumenthenumber:2heinteger:25heinteger:25henumber:3henumber:3

%

%.3f,

12

:Aisacharac255isaninteg55inoctalfo55inhexadec3.141590isa3.141590insc

printf()

print %12.3f

cter.ger.rmis:377.cimalformis:realnumber.cientificform

. .

tf()

32

:ff..

mis:3.141590

1

:

e+00

%12f12

:

f . %12f.

. .

o

.

.

33

doublex;inta;x=3.14159;a=35; printf(x=%f\n,x); => x=3.14159printf(x=%.3f\n,x); => x=3.141printf(x=%10.3f\n,x); => x=3.141printf(x=%d\n,a); => a=35printf(a=%10d\n,a); => a=35

2.10 C.

C. math.h #include.

. double. x,y double n int. .

.

,. sqrt(x) x,x>=0.

exp(x) ex

log(x) ln(x),x>0

log10(x) log10(x),x>0

pow(x,y) xy

fabs(x) |x|

ldexp(x,n) x*2n

34

.!rad. cos(x) x

sin(x) x

tan(x) x

acos(x) x[0,],x[1,1]

asin(x) x[/2,/2],x[1,1]

atan(x) x[/2,/2]

atan2(y,x) y/x[,]

cosh(x) x

sinh(x) x

tanh(x) x

: ,60.

#include#include

intmain(void){

doublex; /*x*/x=60.; /*x*/x=x*3.14159/180.; /*rad*/

printf(cos(60)=%f\n,cos(x)); /**/printf(sin(60)=%f\n,sin(x)); /**/printf(tan(60)=%f\n,tan(x)); /**/

return0; /*main()*/}

35

example.c. :

gccexample.clm

a.out . !!! lm (linkmathematics) . :

cos(60)=0.500001sin(60)=0.866025tan(60)=1.732047

2.11 C#define.

,,C:

:

>

>=

36

:

&& AND()

|| OR()

! NEGATION()

, if, for,while,dowhile. , . 1..:

inta,b,c,d;a=15;b=7;c=25;d=15;

a>101 a>b 1 a>c 0 a>=b 1 ab)||(ab)||(a>c) 1 (a>c)||(d>c) 0 !(a>b) 0 !(a==b)1

37

O:

++ 1

1

++ 1.

++a; a=a+1;a; a=a1;

++

(. , ++a a) (.,a++a).a 1. ++a a , a++ a .toa5

b=a++;b5

b=++a;6.a6.

:

=

= . a=b;ba.

+=

=

38

*= /

/=

%=

:

a+=b; a=a+b;a=b; a=ab;a*=b; a=a*b;a/=b; a=a/b;a%=b; a=a%b;

bits:

& ANDbit

| ORbit

^ XORbit

~ NOTbit

>>

2;

b00011010.

. =3.14159,

39

g=9.81m/sec2 . . . #define. #define:

#define__

. 10cm.

#include#include

#definepi3.14159 /*pi=3.14159*/

intmain(void){

doubleR,S,E; /**/R=10.; /**/S=2.*pi*R; /*pi*/E=pi*pow(R,2.); /*pi*/

printf(S=%fcmE=%fcm^2\n,S,E); /**/ return0;

}

2.12 scanf().

scanf() (). scanf() . .scanf()printf()stdio.h. 2.6scanf().

2.6 a. scanf() 2.4. &, .& . & .

40

scanf(%d,&a);

2.6scanf().

2.4scanf().

d int.c char.s .lf double.f float.c char.

2.7 scanf(). intfloat,.

2.7scanf().

&

a

41

( ):

Pleaseinserttwointegers:1234598765Pleaseinsertonerealnumber:987.654321Theintegersyouhavetypedare:1234598765Therealnumberyouhavetypedis:987.654321

2.13 getchar(),putchar().

, C . getchar() ,putchar() . scanf()printf().

getchar() scanf()charc; charc;c=getchar(); scanf(%c,c);

putchar() printf()

charc; charc;c=k; c=k;putchar(c); printf(%c,c);

putchar() ASCII(2.1).putchar(65)A.

2.14 C.

C . . main(). main() .main().main().

42

, main(). :

intinteger_mod(intx,inty)

{

intresult; result=x%y; returnresult;

}

2.7.

:

.intint.doubledouble.void.

. (AZaz),(09)(_). (+, ,*,/), (), (), (.)#,?,&,@.

... void.intmain(void).

({)(}).

43

., . return.

2.7.

intinteger_mod(intx,inty) /*int,:integer_mod xy*/{

intresult; /*result*/result=x%y; /*resultx%y*/returnresult; /*result*/

}

. . ,(ab) ( c), . :

#include

intinteger_mod(intx,inty); /**/

intmain(void){

inta,b,c; /*a,b,c*/ printf(Eisagetetaakaib:); scanf(%d%d,&a,&b); /**/

c=integer_mod(a,b); /**/ printf(Ypoloipodiairesis%d\n,c); return0;

}

intinteger_mod(intx,inty) {

intresult;result=x%y;returnresult;

}

44

! #include, . .

:

, ,

,(x,yz). (a),.:

#include#include

doublefx(doublex,doubley,doublez); /**/

intmain(void){

doublex,y,z,a; /*a,y,z,a*/

printf(Dosetox:); scanf(%lf,&x); /*x*/ printf(Dosetoy:); scanf(%lf,&y); /*y*/ printf(Dosetoz:); scanf(%lf,&z); /*z*/

a=fx(x,y,z); /**/ printf(a=%f\n,a); return0;

}

doublefx(doublex,doubley,doublez); {

doublee; /*e*/e=pow(x,3.)+pow(y,2.)+z; /**/returne; /**/

}

45

I:

.

3.1 .

C .:

ifelseelseif switch for while dowhile breakcontinue goto

3.2 ifelseelseif.

Cif.if:

if(){ _1; _2; . .}

.,,.

1..if:

if() _1;

46

!if.

ifelse:

if(){ _1; _2; .}else{ _A; _B; .}

, _1, _2 . ,_,_.

,II. ( ), ().if:

doublea,b,c; a=3.4; b=7.8; c=9.2;

if(a

47

ifelseelseif:

if(_1){ _1_1; _1_2; .}elseif(_2){ _2_1; _2_2; .}elseif(_3){ _3_1; _3_2; .}....else{ _A; _B; .}

_1:_1_1,_1_2._2 : _2_1, _2_2 . _3 : _3_1, _3_2 . :_1,_2,_3.,else,_,_.

.elseif.

..scanf(). if 3.1

48

3.1if.

ifelse elseif 3.2

3.2ifelseelseif.

3.3

49

3.33.13.2.

if(?:).:

_1?_2:_3

ifelse,:

if(_1){ _2; }else{ _3;}

3.3 switch.

if .if, . C switch .switch( ) .switch:

switch(){ case_1: _1_1; _1_2; .

50

. break; case_2: _2_1; _2_2; . . break; case_2: _2_1; _2_2; . . break; . . . default: _A; _B; . . break; }

(case) .case. default. case defaultbreakswitch.breakcase.

.17. 3.4. 3.43.5.

51

3.4case.

3.53.4.

52

3.4 for.

.().

for,whiledowhile.,for,:

for(_1;_2;_3){ _1; _2; . . }

for (_1,_2.) : _1,_2_3.:

_1. _2 .

for.for.

_3. _2.

for.for.

_3. _2.

for.for.

_3 _2 ._2for.

for n ( n ).n :_1,_2_3.

: for. 110.

53

#include

intmain(void){ inti; /*i*/

for(i=1;i

54

_2; . . }

for (if()break).

3.5 while.

while for .while:

while(){ _1; _2; . . }

. (_1,_2.)..

:for,while. 110.

#include

intmain(void){ inti; /*i*/

i=1; /*i1*/while(i

55

i.i1.whilei

56

do{ /*dowhile*/ printf(%d\n,i); /*i*/ i++; /*i1*/ }while(i

57

inti; /*i*/ for(i=1;i

58

V:

.

4.1 .

C, , 1972 Dennis Ritchie AT&T Bell Labs. ( Unix). (hardware)..

. . C . , . .

xfloat,3.1415.

floatx; /*xfloat*/ x=3.1415; /*x*/

. ;

(RAM). . ( bytes) ., . , , . .

59

floatx; /*xfloat*/

x. bfffdfe0.

x=3.1415; /*x*/

bfffdfe03.1415.x . &. x &x. printf()x,.

printf(%f\n,x);=> 3.1415

printf(%p\n,&x);=> bfffdfe0

printf() %p. .:

floatx; /*xfloat*/ float*point_x; /**point_xfloat*/

x=3.1415; /*x*/ point_x=&x; /*point_xx*/

RAM

bfffdfe4

3.1415x

bfffdfdc

..

bfffdfe8

bfffdfe0

60

x float. point_x *. , (. x*y), ,.*point_xx. x 3.1415. point_xx.

.

printf() x, x , point_x, point_x *point_x.

printf(%f\n,x); => 3.1415

printf(%p\n,&x); => bfffdfe0

printf(%p\n,point_x);=> bfffdfe0

printf(%p\n,&point_x);=> bfffdfe4

printf(%f\n,*point_x);=> 3.1415

*point_x x. x *point_x . :

*point_x=6.2;

bfffdfe0

RAM

3.1415x

bfffdfdc

bfffdfe8

bfffdfe0

point_x bfffdfe4*point_x

61

x6.2.

(by reference) , (hardware) . internet.

4.2 .

. , . . . .

float2.1,7.2,6.4,9.3, 5.8. .:

floata[5]; /*a*/ a[0]=2.1; /**/ a[1]=7.2; a[2]=6.4; a[3]=9.3; a[4]=5.8;

:

..

. []. n1, n

. a[0] a[4].

! a[5] segmentation fault. ,a[7].

62

. :

bytes.

:

floata[5]={2.1,7.2,6.4,9.3,5.8.}; floata[]={2.1,7.2,6.4,9.3,5.8.};

...

double . 0., 1., 2., .9. for.

inti; /*i*/ doublex[10]; /*x*/

for(i=0;i

63

,, . doublea[10].

inti; /*i*/ doublea[10]; /*a*/

for(i=0;i

64

chara[]=UniversityofIoannina;printf(%s\n,a); /*UniversityofIoannina*/

scanf(),:

charb[20]; /**/ scanf(%s,&b); /*b*/

C. string.h ( #include). a b.:

strlen(a):a. strcmp(a,b):ab.

. >0

65

doublesum(doublea[]){ /*sum()*/doubles; /*s*/s=0.; /*s*/for(i=0;i

66

:

doublea[3][4]={1.2,4.3,7.8,9.3,6.3,8.9,6.7,3.4,1.9,9.8,4.1,6.6};

doublea[][4]={1.2,4.3,7.8,9.3,6.3,8.9,6.7,3.4,1.9,9.8,4.1,6.6};

. ..

. b[3][4][5] 60 .

,,. doublea[3][4]..

doublea[3][4]; /**/inti,j; /*ij*/

for(i=0;i

67

printf(\n); /**/ }

for.....\n(for).

68

V:

.

5.1 .

. ..

C . :

floata; /*float*/intb; /*int*/floatc[3]; /*float*/chard[3]; /**/a=7.1;b=10;c[0]=2.1;c[1]=4.5;c[2]=6.8;d=Hi;

,;.C.:

.:

structmy_example{floata; intb; floatc[3];chard[3];};

( ). my_example..

69

().:

structmy_examples1;()s1 . .

. :

s1.a=7.1; s1.b=10; s1.c[0]=2.1;s1.c[1]=4.5;s1.c[2]=6.8;s1.d=Hi;

, (_._). ., printf(), scanf(),.

:

structmy_examples1={7.1,10,2.1,4.5,6.8,Hi};

. :

structmy_example{floata; intb; floatc[3];chard[3];}s1;

C. .

s1 . .

70

: . (2,3)(4,5)..

.:

structsimeio{ doublex; doubley;

};

:

#include #include

intmain(void){

structsimeio{ /**/ doublex; doubley; };

structsimeioA={2.,3.}; /**/ structsimeioB={4.,5.}; /**/ doublera,rb,rab; /*ra,rb,rab*/

s1.a

s1.b

s1.c[0]

s1.c[1]

s1.d[2]

10

2.1

4.5

s1.d[0]

s1.d[1]

s1.c[2]

\0

i

H

6.8

RAM

7.1

71

ra=sqrt(pow(A.x,2.)+pow(B.y,2.)); /**/ rb=sqrt(pow(B.x,2.)+pow(B.y,2.)); /**/

rab=sqrt(pow(B.xA.x,2.)+pow(B.yA.y,2.)); /**/

printf(ApostasisimeiouAapoarxi=%f\n,ra); /**/ printf(ApostasisimeiouBapoarxi=%f\n,rb); printf(ApostasisimeionAB=%f\n,rab);

return0; }

: N.a=3+5ib=58i.

structmigadikos{ /**/ doublere; doubleim;

}; structmigadikosa={3.,5.}; /*a*/ structmigadikosb={5.,8}; /*b*/

: N .Anagnostou,Dimitrios3241.

,.:

structfoititis{ /**/ chareponimo[20];

charonoma[20]; intAM;

};structfoititisa={Anagnostou,Dimitrios,3241};

20,int.

5.4 .

C . . :

72

structfoititis{ /**/ chareponimo[20];

charonoma[20]; intAM;

};structfoititisA[200];

A[200]..:

A[0].eponymoA[0].onomaA[0].AM

:A[1].eponymoA[2].onomaA[3].AM

..

5.3 .

. migadikos , ..main().

#includestructmigadikos{ /**/

doublere; doubleim;

};voidfx(structmigadikosb); /**/

intmain(void){ structmigadikosa={2.,3.}; /*a*/ fx(a); /*fxa*/ return0; }

voidfx(structmigadikosb){ /**/ printf((%f)+i(%f),b.re,b.im);

}

73

. .. main() a.a.:

voidfx(structmigadikosb)

.voidprintf().

5.4 .

.:

structvarious{ floata;intb;charc;};structvariouss;

unionvarious{ floata;intb;charc;};unionvariouss;

unionstruct..().

s.a

s.b

s.c

RAM

s.a

s.b

s.c

RAM

74

.. .

75

V:

.

5.1 .

scanf() printf(). stdin (standard input), stdout(standardoutput),5.1(a).

. , . . , (5.2(b)).

5.1:a).b).

76

5.2 .

.5.2.

5.2:.

x=3.14159.:

#include

intmain(void){ doublex; /*x*/ FILE*fp; /*fp*/

x=3.14159; /*x*/fp=fopen(arxeio.data,w); /*arxeio.data*/

fprintf(fp,%f,x); /**/ fclose(fp); /**/ return0; }

:

. : FILE*fp; fp ( ) FILE, .

: fp=fopen(arxeio.data,w);

77

fopen():, arxeio.data. , w ( write) .! w arxeio.data...

fprintf(): fprintf(fp,%f,x); fprintf() printf() ().

,fclose(): fclose(fp);

5.3 .

.5.3.

5.3:.

dedomena.txt 7.689. ,,.:

78

#include

intmain(void){ doubley; /*y*/ FILE*pp; /*pp*/

pp=fopen(dedomena.txt,r); /*dedomena.txt*/ fscanf(pp,%lf,&y); /*y*/ printf(y=%f\n,y); /*y*/

fclose(pp); /**/ return0; }

dedomena.txt:

. : FILE*pp;pp ( ) FILE, .

dedomena.txt: pp=fopen(dedomena.txt,r);fopen():, dedomena.txt. ,r(read) . ! dedomena.txt .

dedomena.txt fscanf(): fscanf(pp,%lf,&y); fscanf() scanf() ().

fclose(): fclose(pp);

fopen(), :

w:. r:.

79

a : .

5.2 putc()getc().

C . getc()putc().5.4.

5.4:getc()putc().

getc()putc() . scanf() printf().

getc() scanf()

charc; charc; c=getc(stdin); scanf(%c,&c);

putc() printf()

charc; charc; c=k; c=k; putc(c,stdout); printf(%c,c);

80

getc() putc() ,stdinstdout . getc() putc() .

charc; /*char*/ FILE*fp; /*fp*/

fp=fopen(dedomena.txt,r); /*dedomena.txt*/c=getc(fp); /*c*/fclose(fp); /**/

charc; /*char*/ FILE*fp; /*fp*/ c=k; /*c*/

fp=fopen(arxeio.data,w); /*arxeio.data*/putc(c,fp); /**/fclose(fp); /**/

C fgetc() fputc() getc()putc().

. , ,.EOF(EndOfFile). :

charc; /*char*/ FILE*fp; /*fp*/

fp=fopen(dedomena.txt,r); /*dedomena.txt*/

while((c=getc(fp))!=EOF){ .}

fclose(fp); /**/

81

: while((c=getc(fp))!=EOF){ . } .whileEOF.