Formatted Input and Output

Functions

The standard library functions are predefined functions provided by the C compiler. Using them, specify the header files indicating where to find these functions (include directive)

The function defined by the programmer or the user-defined function are functions created by the programmer / developer for use in a program.




Output Operation
To show data/text on your display, some of the standard libray functions are needed such as:

printf();

Example : 

int main ()

{ printf("Hello World!!!");

}

The output will be : Hello World!!!

Output has formatted specifications:

%[flags][width][.precision]type

Example 

printf("%10s",Algo); >>>>Algo......

printf("%-10s",Algo); >>>>......Algo

printf (“%-8.3f”, 3.14159 );>>>3.141...

putchar();

Example

char ch ='A'

putchar(ch);

output=A

putch();

Output will be Ascii character.

char ch=’b’;

putch(ch);

puts();

puts(”Hello”);

puts(”World”);

Output:

Hello

World

Input Operation

scanf();

Format=int scanf( const char *format [,argument]... );

Example :

int a;

scanf(”%d”,&a); 

Input format=Type

Type

//%d integer

//%f float

//%lf double

//%s string/array of character

//%c single character

//[^...] scan until ...

// [^\n] scan until it find a new line

// [^a] scan until it scan letter a

Multiple variable scanning:

int a,b,c;

total=scanf("%d %d %d",&a,&b,&c);

if your input is more than 3, the total counted value of total will still be 3.

getchar();

Example:

char ch; ch = getchar();

getch(); 

Example:

char buffer[40];

char *ptr;

ptr = gets(buffer);

getche();

gets();

By :Steven

2201852132

Computer Science and Statistics