Input & Output
Nguyen Dung
Faculty of IT - College of Science
Functions I/O
stdio.h
Input:
scanf
gets
getch
getchar
Output
printf
puts
putch
scanf
printf
gets
puts
…
conio.h
getch
getchar
putch
…
Output - printf
List arguments
int printf (const char *format [,argument,…])
string (plain text)
Format string
format specifier
%[flags][width][.prec]type_char
%[flags][width][.prec]
type_char
Code
Out put
d
Integer number
u
Unsigned integer
ld
Long integer
lu
Unsigned long integer
o
Octal
x, X
Hexa
f
Real number: float, double
E, e
Real number: float, double
G, g
Real number: floar, double
c
Character: char
s
String: array char
p
Address
Different???
%[flags][width][.prec]
type_char
int x = 5;
float y = 10;
printf(“x = %d, y = %f, z = %d”, x, y, x + y);
x = 5, y = 10, z = 15
%[flags][width][.prec]type_char
Flag
Description
-
Align left
+
Display sign of number
white space
Display sign of negative number
None
Align right
Width
Description
Precision
Description
n
Minimum number of characters
to be printed
.number
The minimum number of
digits to be written
*
Get from parameter
.*
Get from parameter
None
Depend on number input
None
Depend on number input
%[flags][width][.prec]type_char
int x = -45;
int y = 15;
printf("x = %d\n",x);
printf("y = %d\n",y);
printf("y = %+d\n",y);
printf("x = %5d\n",x);
printf("x = %-5d\n",x);
printf("y = %5d\n",y);
x
y
y
x
x
y
=
=
=
=
=
=
-45
15
+15
-45
-45
15
%[flags][width][.prec]type_char
int x = -145;
float y = -10.13596;
printf("x = %010d\n",x);
printf("y = %7.2f\n",y);
printf("y = %12.5f\n",y);
printf("-y= %012.5f\n",-y);
printf("y = %-3.3f\n",y);
printf("y = %*.*f\n",8,3,y);
x = -000000145
y = -10.14
y =
-10.13596
-y= 000010.13596
y = -10.136
y = -10.136
Output – putch, puts
int putch(int ch)
int puts(const char *s)
char ch=„a‟;
putch(ch);
putch(68);
puts(“hello world!”);
a
D
helloworld!
_
In - scanf
int scanf(const char *format [, address,…]);
int x,y;
printf(“Enter x,y: ");
scanf("%d %d",&x,&y);
printf("x = %d\ny = &d",x,y);
Enter x, y: 10_4
x = 10
y = 4_
In - gets
gets(char *s)
Micheal Balack
Name is: Micheal Balack
char name[30];
gets(name);
printf(“Name is: %s”,name);
But
Micheal Balack
Name is: Micheal
char name[30];
scanf(“%s”,name);
printf(“Name: %s”,name);
In – getch, getchar
int getchar(void);
int getch(void);
Input a character: c
Character is entered: c
int ch;
printf(“Input a character: ”);
ch = getchar();
printf(“Character is entered: %c”,ch);
Different:
getchar – display the character entered.
getch – don‟t display.
Exercises
Available:
nguyendung622.wordpress.com
Dealline: 19h before the
learning day of next week.
Send to:
[email protected]
The end