T?p?? ?ed?

1
T?p?? ?ed?µ????

• signed/unsigned, long/short
• µetat??p? t?p?? (a?t?µata ?a? casting)
• char
• enum
• typedef
• strings
• struct

2
?as???? T?p?? ?ed?µ???? C

• T?p?? ?e?e??? ?ed?? ??µ?? ???ad??e?
• char, 1byte a..z A..Z0..9 28 ? 256
• int, 4 bytes -231..231-1 232
• float, 4 bytes 10-37..1038 232
• double 8 bytes 10-307..10308 264
• de??t?? 4 bytes d?e????se?? 232
• (0..232 -1)

3
????? ?as???? T?p?? ?ed?µ????

• int
• ?ed?? ?e?e??? ??p??
• -215..215-1 2 bytes short (µe p??s?µ?)
• 0..216-1 2 bytes unsigned short
• -231 .. 231 4 bytes int (µe p??s?µ?)
• 0 .. 232-1 4 bytes unsigned
• -263..263-1 8 bytes long (µe p??s?µ?)
• 0..264-1 8 bytes unsigned long\
• signed/unsigned ?d?? µe?e??? d?af??et???
  s?µas?a! s?es? signed µe unsigned

4
????? ?as???? T?p?? ?ed?µ????

• char
• ?ed?? ?e?e??? ??p??
• -27..27 1 byte char (µe p??s?µ?)
• 0..28-1 1 byte unsigned char
• float, double
• ?ed?? ?e?e??? ??p??
• 10-37 .. 1038 4 bytes float
• 10-307 .. 10308 8 bytes double
• 10-4931..104932 16 bytes long double

5
?e?????sµe?? ?ed?? ??µ??

• ?a???
• A?apa?astas? (round-off error)
• p? 0.1000001 a?t? 0.1 ?
• epa?a?aµßa??µe?? round-off error µe?e????e? ?a???
• ?s?t?ta/a??s?t?ta x0.1, 0.999999866, 0.1000001
  
• ?pe??e???s? (overflow)
• char y (char) 255
• y
• Yp????? (underflow)
• 0.0 a?t? 0.000000000000000000000000..001 (45 0s)

6
?e?????sµe?? ?ed?? ??µ??

• ?? ?a s?µße?
• unsigned w 0, x 0xffffffff
• --w
• x
• ?? e??a? ? de?ad??? t?µ? t?? y ?a? z
• int y 0xffffffff
• unsigned z 0xffffffff
• ???s??? µe s?es?a???? te?este?

7
Metat??p? ??p??

• Se a???µ?t??e? e?f?ase?? (a?t?µata) e?a
  te?esta??? µetat?epete se a??? t?p? ea? ?pa??e?
  a???? te?esta??? p?? e??a? p?? de??a st??
  a??????? d?ata?? char int float double
  int x2float y3.0 y/x
  gt 3.0/2.0

8
Metat??p? ??p??

• Se a?a?es? (a?t?µata) ? t?µ? sta de??a t??
  µetat?epete st?? t?p? t?? µetaß??t?? sta a??ste?a
  t?? int x 3.14 / 3 / float
  x (2/3) / 0.0 /
• Casting (??t? µetat??p?) float x(float) 2/3
  /2.0/3, 2.0/3.0, 0.66666/ float x (float)
  (2/3) / 0 /

9
char

• ?a?e ?a?a?t??a? a?t?st???e? se e?a µ??ad???
  ??d???
• C ßas??eta? st? ASCII code
• a?faß?t????, ??f?a???, e?d???? (\n, \t...)
• 0 48, 1 49,.., 9 57
• A 65, , Z 90
• a 97, , z 122

10
char

• tµ?µa p????aµµat?? p?? t?p??e? t??? ??f?a????
  ?a?a?t??e? ?a? t?? a?t?st???e? a?e?a?e? t?µe?
  t???
• int j
• for(j0jlt9j)
• printf(c d\n, (char) j, j)

11
?pa???µ?t?? ??p??(Enumerated Types)

• enum boolean_e FALSE, TRUE
• enum boolean_e x / t?p?? enum boolean_e/
• if (x FALSE)

12
?pa???µ?t?? ??p??(Enumerated Types)

• S??ta??enum onoma name0, name1, , name n
• S?µas?a
• e?a s????? a?e?a??? sta?e???
• p??t? sta?e?? apa???µ?s?? a?apa??st?ta? ?? 0, ?
  de?te?? ?? 1 ?t?
• ???sµ?? apa???µ?t?? µetaß??t??
• enum enum_onoma onoma
• p? enum boolean_e y

13
?pa???µ?t?? ??p??(Enumerated Types)

• Sta?e?e? apa???µ?s?? µp????? ?a ???s?µ?p???????
  µe a????? t?p??? - µeta?e??????ta? sa? a?e?a?e?
  sta?e?e?
• ?etaß??te? t?p?? apa???µ?s?? µeta?e??????te sa?
  a?e?a?e? µetaß??te?
• ?e? ???eta? e?e???? ??a t?? t?µe? a?a?es??
• O?s?ast??a e??a? sta?e?e?
• ??????ta? s?????? µeta t?? sta?e?e? (global scope)

14
?pa???µ?t?? ??p??

• S??ta??
• enum onomaname0constant, name1,..
• enum month_eJAN1, FEB, MAR, APR, MAY, JUN, JUL,
  AUG, SEP, OCT, NOV, DEC
• JAN 1, FEB 2 ?t?
• for(iJANiltDECi)printf(d\n,i
• p? enum incase_e NONE0, IN11, IN22, IN123,
  OUT4, EMPTY0

15
?pa???µ?t?? ??p??(Enumerated Types)

• ?p?t?epete ???s? e??? ???µat?? µ??? se e?a enum
  (??? se a??? enum ??te ?a? define)
• ?e? ep?t?epeta?
• enum day_eMon, Tue, Wed, Thu, Fri, Sat, Sun
• enum weekday_eMon, Tue, Wed, Thu, Fri

16
typedef

• typedef unsigned int nsint
• nsint x
• S??ta?? typedef type new_type
• S?µas?a new_type e??a? ?e? ???µa ??a t?? t?p? µe
  ???µa type.
• X??s?µ? ??a ap?f??? µe?a??? ???µat?? t?p?? (p??
  a???ß? pe????af?)
• ??a? t?p?? µp??e? ?a e?e? p???a ???µata

17
typedef

• typedef enum boolean_e boolean_t
• boolean_t x
• typedef unsigned int nsint
• typedef nsint ID_TYPE
• nsint
• foo(nsint x, unsigned int y, ID_TYPE z)...

18
strings

• string e??a? e?a? p??a?a? µe ?a?a?t??e? p??
  te?e???e? µe t?? ?a?a?t??a NULL \0
• char tnameyia sou
• char tnamey, i, a, , s, o, u,
  \0
• yia sou ap?te?e?ta? ap? 8 ?a?a?t??e?
• printf(s,tname)
• scanf(s,tname)/p??s??? \0 p??ste?e? st?
  te???/
• string pointer s?ed?? pa?ta epe?e??as?a strings
  ???eta? µe string pointer char

19

• int
• strlen(char p)
• int length
• for(length0p!NULLp,length)/den metra
  NULL/
• return length
• char tnameyia sou
• char pname tname
• char ps epl 131
• printf(String s has length d characters\n,
• tname,strlen(tname))

20

• int
• strlen(char p)
• int length0
• while(p!NULL)
• length
• p
• return length

• int
• strlen(char p)
• int length0
• while(p!NULL)
• length
• return length

21

• int
• strlen(char p)
• char t p
• while(p)
• return (int) (p-t)/sizeof(char)

22
p?? d?aßa???µe µ?a ??aµµ? se string

• G?a?ete t?? s??a?t?s? int getline(char s,
  int lim) p?? d?aßa?e? µ?a ??aµµ? ap? t??
  e?s?d?. ? ??aµµ? ap????e?eta? st?? p??a?a
  ?a?a?t???? s p?? e??a? pa?aµet??? t?? s??a?t?s??.
  To µe??st? µe?e??? ??aµµ?? ????eta? µe t? lim. ?
  s??a?t?s? ep?st?efe? t? µ???? t?? ??aµµ??.

23

• int
• getline(char s, int limit)
• int c, k
• for(k0kltlimit-1 (cgetchar())!\n
  c!EOF)
• skc
• if (c\n)
• skc
• k
• sk\0
• return k

24
strings

• ???? ???s?µ? ß?ß??????? ltstring.hgt

25
??µe?/struct(ures)???sµ?? t?p??

• struct ep?t?epe? t?? ???sµ? s???et?? t?p??
  ded?µe???
• struct student_s
• char name80
• int id
• int etos
• float vathmos

26
struct o??sµ?? µetaß??t??

• struct student_s
• char name80
• int id
• float vathmos
• struct student_s student
• typedef struct student_s student_t
• student_t student_tableSTUDENT_NUM

27
struct a?af??a se µe??

• student.id 123456
• if (student_tablei.vathmos gt8.0)
• very_good_grade
• for(i0iltSTUDENT_NUMi)
• printf(s 6d 5.2f,student_tablei.name,
  student_tablei.id, student_tablei.vathmos)

28
struct a?a?es?

• ?p?t?epeta? a?a?es? µeta?? µetaß??t?? t?p??
  structs
• student_tableistudent_tablej
• a?t???afe? ?a?e t?µ? t?? j st? i
• a???, ?d?a?te?a ??a pa?aµet????. p??t?µ?te??
  pa???ate/ep?st?efeta? de??t?
• void display_student(student_t s) a?t?
  void display_student(student_t s)

29
struct pointers

• void
• display_student(student_t s)
• printf(s 6d 5.2f,s.name, s.id, s.vathmos)
• a?af??a se µe?? struct µe de??t?
• de??t??-gtµe???
• void
• display_student(student_t s)
• printf(s 6d 5.2f,s-gtname, s-gtid,
  s-gtvathmos)

30
structa?af??a se µe?? µe de??t?

• for(i0iltSTUDENT_NUMi)
• display_student(student_tablei)
• student_t s,p
• ...
• if (s-gtid ! p-gtid)...