lecture 3 data types 1

8/10/2019 Lecture 3 Data Types 1

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Fundamental

data types


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#include

int main(void)

{

int a, b, c;

float x = 0.0f, y = 3.3f, = !"."f;

$intf( %&nut t'o intee$s * );

scanf( %+d+d*, b, c );

a = b - c;

x = y - ;

$etu$n 0;

/ecla$ation/ecla$ation 'ith initialiation

always initialize!!!

unction calls

1ssinment

statements


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undamental data tyes

2 &nte$al (sined o$ unsined) cha$

sho$t

int lon

2 loatin oint tyes float

double


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Long formLon

g form

char signed char unsigned char

sined shortint sined int sined longint

unsigned shortint unsignedint unsigned longint

float double long double

Common (short) formCommon

(short) form

cha$ sined cha$ unsined cha$

sho$t int lonunsined sho$t unsined unsined lon

float double lon double

undamental /ata yes


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unctionality 4$ous

Integral Types:Inte

gral Types:

cha$ sined cha$ unsined cha$

sho$t int lon

unsined sho$t unsined unsined lon

Floating Types:Floatin

g Types:

float double lon double

rithmetic Types:rithmetic T

ypes:2 inte$al tyes

2 floatin tyes


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5onstants

char a, x, 0, &, \n

int 1, 0, -54, 4234567

long 0l, 123l, 7766L

unsigne 0u, 23u, 3000000000!

"loat 1#2", #2", 1#", 3#1415$"

ou%le 1#0, -3#1412long ou%le 1#0l, 2#4433l


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cha$acte$ 6a6 6b6 6c6 ... 66

intee$ value 7" 78 77 ... 99:

cha$acte$ 616 66 656 ... 66

intee$ value " ... 70

cha$acte$ 606 696 6:6 ... 676

intee$ value ?8 ?7 0 ... "

cha$acte$ 66 6@6 6-6

intee$ value 38 ?: ?3

Aome 5ha$acte$ 5onstants

and thei$ &ntee$ Balues

he cha$acte$ C0C

has a value of ?8


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ame of Character "ritten in C Integer #alue

alert CDaE $

bac%slash &'' *

horizontal tab &'t

newline &'n +,

null character &', ,

-uote &'. /

he cha$acte$

CD0C has a

value of 0


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cha$ c = 6a6;

$intf(F+cF, c);

$intf(F+dF, c);

$intf(F+c+c+cF, c, c-9, c-:);


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cha$ c = 6a6;

$intf(F+cF, c);

$intf(F+dF, c);

$intf(F+c+c+cF, c, c-9, c-:);

ais $inted

$7is $inted

a%cis $inted


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and thei$ &ntee$ Baluescha$acte$ 616 66 656 ... 66


cha$ c = 0;

int i = 0;

fo$ ( i = 6a6; i


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and thei$ &ntee$ Baluescha$acte$ 616 66 656 ... 66


cha$ c = 0;

int i = 0;

fo$ ( i = 6a6; i


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Gse$ /efined 5onstants

#include

int main(void)

{

int c = 0;

'hile ( ( c = etcha$() ) H= 23F)

{

utcha$( c );

utcha$( c );

$etu$n 0;

Ioo until the 2nd 3f the File

in stdio1haea$ the line 4define

23F (5+)


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5onstants

Type 6escription 27ample

char single character &g

special character &'n

he7adecimal code &'7+a

int decimal 5+8 *8 ,8 +*/9;

octal ,+,8 5,*,8 ,=85?e7p +*/e5*8 +*1/e5*


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/ecimal, Jexadecimal, Kctal

conve$sions#include

int main(void)

{

$intf( %+d +x +oDn*, 97, 97, 97 );

$intf( %+d +x +oDn*, 0x9c, 0x9c, 0x9c);

$intf( %+d +x +oDn*, 09", 09", 09");

$intf( %+dDn*, 99 - 0x99 - 099);

$intf( %+xDn*, :07"99);$intf( %+dDn*, 0x9ff);

$etu$n 0;


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/ecimal, Jexadecimal, Kctal

conve$sions#include

int main(void)

{

$intf( %+d +x +oDn*, 97, 97, 97 );

$intf( %+d +x +oDn*, 0x9c, 0x9c, 0x9c);

$intf( %+d +x +oDn*, 09", 09", 09");

$intf( %+dDn*, 99 - 0x99 - 099);

$intf( %+xDn*, :07"99);$intf( %+dDn*, 0x9ff);

$etu$n 0;

97 93 :3

:8 9c 3?

9 f 9"

3"

9fffff

:07"99


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comute the sie of some

fundamental tyesinclue stio#h.int /ainoi

rint"he sie o" so/e "una/ental tes isco/ute#\n\n8

rint"char9 :3 %te \n, sieo"char 8

rint"short9 :3 %tes\n, sieo"short 8

rint"int9 :3 %tes\n, sieo"int 8

rint"long9 :3 %tes\n, sieo"long 8

rint"unsigne9 :3 %tes\n, sieo"unsigne 8

rint""loat9 :3 %tes\n, sieo""loat 8

rint"ou%le9 :3 %tes\n, sieo"ou%le 8 rint"long ou%le9:3 %tes\n,sieo"long ou%le 8

return 08

;

sieof $etu$ns the

numbe$ of bytes

$ese$ved fo$ a

va$iable tye.


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fundamental tyes$un on %L5 Lentium 3F

he sie of some fundamental tyes is comuted.

cha$ 9 byte

sho$t : bytes

int ? bytes

lon ? bytes

unsined ? bytesfloat ? bytes

double 8 bytes

lon double 8 bytes


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fundamental tyes

sieof(cha$) == 9

sieof(sho$t)


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4oin ove$ the Iimit

inclue stio#h.

inclue li/its#h.

int /ain oi

int i < 08

unsigne u < !=>?@'A8

"or i < 08 i 58 BBi

rint" :u B : < :u\n, u, i, u B i 8

"or i < 08 i 58 BBi

rint" :u C : < :u\n, u, i, u C i 8

return 08

;

yically eMual to 0x == :3:!9 ==

9*9;$*


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4oin ove$ the Iimit

$un on Fsco$ioF

?:7?7":7 - 0 = ?:7?7":7

?:7?7":7 - 9 = 0

?:7?7":7 - : = 9?:7?7":7 - 3 = :

?:7?7":7 - ? = 3

?:7?7":7 @ 0 = 0

?:7?7":7 @ 9 = ?:7?7":7

?:7?7":7 @ : = ?:7?7":7?

?:7?7":7 @ 3 = ?:7?7":73

?:7?7":7 @ ? = ?:7?7":7:

he va$iable $esta$ts itself


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&ntee$s6 Ne$esentation

Type @alue Ainary @alue

unsigne char unsigne char 0 0000 0000unsigne char 255 1111 1111unsigne char 127 0111 1111

unsigne char 12+ 1000 0000signe char s signe char 0 0000 0000signe char -1 1111 1111 (*Bs complement)signe char 127 0111 1111signe char -12+ 1000 0000 (*Bs complement)

signe short s signe int s

@ means @alues means sign

negati@e integers 5in

*Bs complement


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&ntee$s6 Ne$esentation (:)

sined cha$ sc = !9:8;

unsined cha$ uc = :;

sc = sc ! 9;

uc = uc - 9;

uc = :;

uc = uc@:;

+,,, ,,,,

++++ ++++

,+++ ++++ D +*$ Enderflow

,,,, ,,,, D , 3@erflow

++++ ++++

++++ +++, D *9


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loatin yes

foat single-precision foating-pointdouble double-precision foating-point

long double extended-precision foating-point

Type SmallestPositiveValue

LargestValue

Precision

foat 1.17*10-38 3.40*1038 6 digits

double 2.22*10-308

1.79*10308

15 digits

double x longdouble x

scan!"#$l!%& 'x(# %


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loat $e$esentation ! limited

accu$acyinclue stio#h.

int /ain

int i8

"loat " < 08

"or i < 08 i 1008 BBi

" B< 0#018

rint" :"\n, " 8

return 08

; 3utput: ,1


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Aecial float values

2 a ot a umber1 Ne$esents an illeal value

rint":"\n, sDrt-18'ill $int-1#=>E00or nan

2 IF infinity

rint":"\n, 1F0#08'ill $int1#=>G00or in"


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Oathematical unctions

s-rt(7)

pow(78y) D 7y

e7p(7) DeG

log(7)sin(7)

cos(7)

tan(7)

he functions a$e decla$ed in

1ll the functions use doubles

(floats sM$tf, o'f,exf,...)

NeMui$es linPin 'ith math lib$a$y

gcc -l/


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inclue stio#h.

inclue /ath#h.

int /ainoi

ou%le x < 08rint" \nhe sDuare root o" x an x raise

\nto the x oHer Hill %e co/ute#\n---\n\n 8

Hhile 1

rint"=nut x9 8

scan":l", &x 8

i" x .< 0#0

rint"\n:15s:22#15e\n:15s:22#15e\n:15s:22#15e\n\n

,x < , x, sDrtx < , sDrtx,

oHx, x


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he Nesult of the L$o$am

he sDuare root o" x an x raisehe sDuare root o" x an x raiseto the x oHer Hill %e co/ute#to the x oHer Hill %e co/ute#

------

=nut x9 2=nut x9 2

x < 2#000000000000000eB00x < 2#000000000000000eB00

sDrtx < 1#4142135623730$5eB00sDrtx < 1#4142135623730$5eB00

oHx, x < 4#000000000000000eB00oHx, x < 4#000000000000000eB00

=nut x9=nut x9


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he usual a$ithmetic conve$sion ($omotion)

2 If eitheroperand is of type long double8 double8 floator unsigned long8 the

other operand is converted to long double8 double8 floator unsigned longappropriately1

2 3therwise8 the integral promotions are performed on both operands8

and the following rules are applied:

2 If one operand has type longand the other operand has type unsignedthen

one of two possibilities occurs:Q If a long can representall the @alues of an unsigned8 then the

operand of type unsignedis convertedto long1

Q If a longcannot representall the @alues of an unsigned8 then

bothoperands are convertedto unsigned long1

2 3therwise8 if either operand is of type long8 the other operand is converted

to long1

2 3therwise8 if either operand is of type unsigned8 the other operand is

convertedto unsigned1

2 3therwise8 both operands ha@e type int1


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Rx$essions and yes

char c8 short s8 int i8 unsigne u8 long l8unsigne long ul8"loat "8 ou%le 8 long ou%le l8

27pression Type 27pression Type

c s H i int u $ i unsigned

u *1, i double f $ i float

c = / int $ s ul unsigned long

c = 1, double ld = c long double

d = s double u ul unsigned long

* i H l Long u l systemdependent


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5ast

ou%le < 3#38int i < 08

unsigne ui < 08

char c8

i < int8

< ou%lei F 28

ui < unsignei8

c < ++28

i DD trunc(d) D /

d DD +1


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lecture 3 data types 1

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