2. • Dev-C++:
•
•
•
•
•
2

3. Dev-C++
•
File > New > Source File
•
• .c
 first.c
3

4. Dev-C++
•

 F9
• :
 getch()
4

5. main
stdio.h
#include <stdio.h>
int int main()
{
int a, b, sum;
printf() printf("Enter A: "); int
scanf("%d", &a); a, b sum
printf("Enter B: ");
scanf("%d", &b); scanf()
sum = a+b;
printf("Sum = %dn", sum);
getch();
return 0;
}
0
;
5

6. (Comment)
•
• /* …
( )… */
// …
( )…
/* arithmetic
expression */
// create 6

7. a
(Beep)
n (newline)
backslash
’
7

8. (address) (data)
0000 32 1 =1 8
0001 67
0002 255
0003 0
0004 121
: :
8

9. ( )
char 1 -128 +127
short 2 -32,768 +32,767
int
2 -32,768 - +32,767
4 2,147,483,648 +2,147,483,647
long 4 -2,147,483,648 +2,147,483,647
float 4 3.4 * 10-38 3.4 * 1038
double 8 1.7 * 10-308 1.7 * 10-308
9

10. (Variable)
•
 ( )
: :
short a, b, sum; 1000 10
2 a
a = 10; 1001 30
0
b = 5; 1002 211
5 b
sum = a+b; 1003 0
5
1004 15
8 sum
1005 23
0
: :
b 5 )
&b 1002
10

11. (Variable)

underscore ( _ )

underscore ( _ )
 1-32
 $
 Case sensitive

Reserve words 11

12. C
auto double int struct
break else long switch
case enum register typedef
char extern return union
const float short unsigned
continue for signed void
default goto sizeof while do
12

13. type variable-list [=value] ;
• variable-list
(,)
 type
 value 13

14. int a=1;
int lower;
float man,ratio;
double point;
char ch,c=„5‟,name;
14

15. #include <stdio.h>
#define PI 3.414 const.c
int main()
{
3.414
printf("%.3f",PI);
getch();
return 0;
}
15

16. •
•
short arr[3]; : :
arr[0] = 50; 0020 50
2 arr
arr[2] = 89; 0021 30
0
0022 211
arr 20 0023 5
arr[0] 50 0024 89
8
arr[1] 211 0025 23
0
arr[2] 89 0026 33
0027 12
: :
16

17. • “ ”
(array of char)
char s[5] = "Hello";
printf("%c %c %cn", s[0], s[1], s[2]);
0 1 2 3 4
S H e l l o
:
H e l
17

18. /
• ( /
)
“stdio.h”
•
 scanf (
%format)
• (Output
Function)
 printf (
%format) 18

19. •
• printf
int c = 65; :
2
printf("c (as a number) = %dn", c);
30
printf("c (as a character) = %cn", c);
65 c
5
: 8
c (as a number) = 65 23
c (as a character) = A :
19

20. %format scanf
printf
%for
mat
int %d
long %ld
long long %lld
unsigned int %u
unsigned long %lu
unsigned long long %llu
float %f
double %lf
char %c
char array[] %s
20

21. scanf
char name[20];
int age;
printf("Enter your name and age: ");
scanf("%s %d", name, &age);
printf("Hello %s. You are %d years old.n",
name, age);
:
Enter your name and age: Tony 38
Hello Tony. You are 38 years old.
21

22. •
START
Statement1
Statement2
START
Statement3
Statement
END Statementn
END
22

23. Relational Operators
•
(Operand)
Operator
<
<=
>
>=
==
!=
23

24. Expression
•
(Operand)
(Operator)
A = 10; B = 3; C = 20;
Expressio
n
A+B 13
(A + B) – C -7
(C*B)+(A*B) 90
A%B 1
C%B 2
24

25. Relational Operators
• Relational
Operators
i = 1; j = 2; k = 3;
Expression
i<j true 1
(i + j) >= k true 1
(j + k) > (i + 5) false 0
k != 3 false 0
j == 2 true 1
25

26. Logical (Bitwise) Operators
•
(Operand)
Operator Operator)
(Logical
&& AND
|| OR
26

27. AND Operators
•
A B A && B
True True T && T True 1
True False T && F False 0
False True F && T False 0
False False F && F False 0
27

28. AND Operators
• AND Operators
i = 8; j = 4.5; k = „z‟; // ascii z 122
Expression
(i >= 6) && (k == „z‟) T && T == T 1
(i >= 6) && (k == 122) T && T == T 1
(j >= 0) && (j != 4.5) T && F == F 0
(k > 0) && (j != 5) T && T == T 1
(i < 0) && (j > 0) && (k > 0) F && T && T == 0
F
28

29. OR Operators
•
A B A || B
True True T || T True 1
True False T || F True 1
False True F || T True 1
False False F || F False 0
29

30. OR Operators
• OR Operators
i = 8; j = 4.5; k = „z‟; // ascii z 122
Expression
(i >= 6) || (k == „z‟) T || T == T 1
(i >= 6) || (k != 122) T || F == T 1
(j < 0) || (j != 4.5) F || F == F 0
(k > 0) || (j != 5) T || T == T 1
30

31. •
i = 7; f = 4.5;
Expression
f>5 False 0
!(f > 5) True 1
i <= 3 False 0
!(i <=3) True 1
i > (f + 1) True 1
!(i > (f + 1)) False 0
31

32. (Precedence)
•
Operators
unary operators - , ++ , -- , ! , sizeof() R->L
multiply, divide and *,/,% L->R
remainder
add and subtract +,- L->R
relational < , <= , > , >= L->R
equality == , != L->R
32

33. (Precedence)
•
Operators
and && L->R
or || L->R
assignment operators =, +=, -=, *=, /=, %= R->L
33

34. i = 8; j = 4.5; k = „z‟; // ascii z 122
Expression
i + j <= 10 False 0
i >= 8 && k == „z‟ True && True == True 1
k != „a‟ || i + j <= 10 True || False == True 1
k != „a‟ || i < j && k < i True || False && False 0
== True && False
== False
k != „a‟ || i < j && k < i True || False && False 1
== True || False
== True 34

35. •
 if
 if…else
 if
 switch-case
•
 while loop
 do…while loop
 for loop
• 35

36. if
C Syntax Flowchart
if (condition) START
{
statement1;
: true
condition
statementN;
} false Statement
• condition Statement
int
• {} END
condition
• 36

37. if
#include <stdio.h> if1.c
int main()
{ I>J
int i=101,j=100;
if(i>j)
printf("I > J");
getch();
return 0;
} 37

38. if…else
Flowchart C Syntax
START if (condition)
{
true false statementt1;
condition
statementt2;
Statementt1 Statementf1
}
else
Statementt2 Statementf2 {
statementf1;
statementf2;
END }
38

39. if…else
#include <stdio.h> ifelse1.c
int main()
{ I <= J
int i=101,j=102;
if(i>j)
printf("I > J");
else
printf("I <= J");
getch();
return 0;
}
39

40. if
if (x==1)
true Action1;
x==1 Action1;
false
else if (x==2)
x==2
true
Action2; Action2;
false else if (x==3)
true
x==3 Action3; Action3;
false
true
else if (x==4)
x==4 Action4;
false
Action4;
Default_Action; else
Default_Action;
40

41. if
#include <stdio.h> ifelse2.c
int main()
{ >6
int i=7;
if(i>7) printf("> 7");
else if(i>6) printf("> 6");
else if(i>5) printf("i> 5");
else printf("1 , 2 , 3");
getch();
return 0;
}
41

42. switch-case
switch (x)
x==1
true
Action1;
{
case 1: Action1;
false
true break;
x==2 Action2;
case 2: Action2;
false
true
break;
x==3 Action3;
case 3: Action3;
false
true
break;
x==4 Action4; case 4: Action4;
false break;
Default_Action;
default: Default_Action;
break;
}
42

43. switch-case
#include <stdio.h>
int main() switch1.c
{
int i=2;
switch(i)
{
2
case 2 : printf("2");
break;
case 1 : printf("1");
break;
default : printf("NO MATCH");
break;
}
getch();
return 0;
} 43

44. i++ = i
= i--1 =
i+ i = i-
1
i+=5 = i=
i+i-=5 =
5 i = i-
5 44

45. while
while (condition) START
{
stmt1;
stmt2;
: false
condition
stmtN;
} true
Statement
• stmt1
stmtN Statement
condition
END
45

46. Counting
Loop)
•
•
int i, sum = 0;
i = 1;
while (i <= 10)
{
sum = sum + i;
i = i + 1;
}
printf("Sum = %dn", sum);
46

47. while
#include <stdio.h>
int main()
while1.c
{ Hello 1
Hello 2
int i=1; Hello 3
while(i<=10) Hello 4
{ Hello 5
Hello 6
printf("Hello %dn",i); Hello 7
i++; Hello 8
} Hello 9
Hello 10
getch();
return 0;
} 47

48. while
(INFINITY LOOP)
#include <stdio.h>
int main() while2.c
{ Hello 1
int i=1; Hello 2
while(1) Hello 3
{ Hello 4
printf("Hello %dn",i); Hello 5
if(i==10) Hello 6
Hello 7
break; Hello 8
i++; Hello 9
} Hello 10
getch();
return 0;
} 48

49. do…while
do START
{
stmt1;
stmt2;
: Statement1
stmtN;
} while (condition);
StatementN
• stmt1...stmtN
true
condition
condition false
•
END
stmt1...stmtN
49

50. do…while
#include <stdio.h>
dowhile1.c
int main()
{ Hello 1
int i=1; Hello 2
do Hello 3
Hello 4
{ Hello 5
printf("Hello %dn",i); Hello 6
i++; Hello 7
} Hello 8
while(i<=10); Hello 9
getch(); Hello 10
return 0;
}
50

51. for
•
for (init_stmt; condition; update_stmt)
{
statement1;
statement2;
:
statementN;
}
•
1. init_stmt
2. condition
statement1...statementN
51

52. for
START
init_stmt
for (init_stmt; condition; update_stmt)
{
statement1;
false
statement2; condition
:
statementN;
}
true
Statement1
StatementN
update_stmt
END
52

53. for
#include <stdio.h>
int main() for1.c
{ Hello 1
Hello 2
int i; Hello 3
for(i=1;i<=10;i++) Hello 4
{ Hello 5
Hello 6
printf("Hello %d",i); Hello 7
printf("n"); Hello 8
} Hello 9
Hello 10
getch();
return 0;
} 53

54. (Subroutine)
• (Function)
•
•



 54

55. • (Standard
Functions)

 printf(), scanf(), ...
• (User Defined
Functions)

 main()
55

56. scanf, printf,
stdio.h
gets, puts
math.h sin, cos, exp, pow
isalpha, isdigit,
ctype.h
islower, isupper
string.h strlen, strcpy,
strcmp
stdlib.h rand, atoi, atof
56

57. • void say_hi(char *name)
{
 printf("Hi, %sn", name);
void }

return
int max(int a, int b)
{
• if (a > b)
return a;
else
 return b;
}
 return
57

58. #include <stdio.h>
int incr(int i)
{
int j;
function1.c
j = i + 1;
return j;
}
int main()
{
int k, m = 4;
k = incr(m);
printf ("k = %d, m = %dn", k, m);
getch();
return 0;
}
58

59. (Function)
#include <stdio.h>
void print1()
{
printf(“Hello”);
function2.c
printf(“n”);
}
int main()
{
print1();
print1();
getch();
return 0;
}
59

60. (Function)
#include <stdio.h>
float cal_tax(float i)
{
function3.c
float ctax;
ctax = i*0.07;
return ctax;
}
int main()
{
float money=7290,ff;
ff = cal_tax(money);
printf(“%f”,ff);
getch();
return 0;
}
60

61. •
•
61

62. •
Enter N: 3 Enter N: 5
* *
** **
*** ***
****
*****
62

63. #include <stdio.h>
int main ()
{ i scanf
int i;
scanf("%d", i);
if (i = 0)
puts("false"); (=)
else
puts("true");
(==)
return 0;
}
63