What is Input Output in C Language .

Input and Output (I/O)

In this you will learn to use scanf() function to take input from user and printf() function to display the result to the user.

C Output

In C programming, Printf() funcation is the main output function to display result to user. The function sends formatted output to the screen.

Example 1 : C Output 

                                                                                                                                                                                                                                                                                                                                                                                                                         

Output
C Programming

How does this program work

• All valid C program must contain the main()  function.The codes execution begins from the start the main() function.
• The printf() is a library function to send formatted output to the screen. The function prints the string inside the quotations.
• To use prinf() in our program, we need to include stdio.h  header file the #include<stdio.h> statement.
• The return 0; inside the main() function is the " Exist status " of the program.

Example 2 : C Integer Output 

  

                                                                              

Output
Number =5

We use %d specifier to print int types. Here, the %d inside the quotations will be replaced the value of testInteger.

Example 3 : C float and double Output

Output

number1 = 13.5000

number2 = 12.4000

To print float, we use %f  format specifier, similarly we use %if to print double

values.

Example 4 : C print character

Output
character = a

To print char , we use %c format specifier.

Input

In C programming, scanf is one of the commonly used function to take input from the user. The scanf() function reads formatted input from the standard input such as keyword. 

Example 5 : C integer Input/Output

Output 

Enter an integer : 4

Result 

Number = 4 

Here, we have used %d format specifier inside the scanf() function to take int from the user. When the user entered an integer, it is stored  in the testinteger variable.

Example 6 : C float and double Input/Output

Output
Enter a number =12.54

Enter another number =34.54

num1=12.54
num2=34.54

We use %f and %if format specifier for float and double respectively.

Example 7 : C Character Input/Output

Output
Enter a character : a
You entered a

When a character entered by the user in the above program, the character itself is not stored. Instead, an integer value ASCII is stored.
And when we display that value using  %c text format, the entered character is displayed. If we use %d to display the character, its ASCII value is printed.

Example 8 : C ASCII value Input/Output

Output
When a character :g
you entered :g
ASCII value is 103

Input/Output Multiple Values

Output

Enter integer and then float :  -3

3.5

You entered -3 and -3.50000

Format Specifier for I/O

• %d      <=====>    Interger_value
• %f       <=====>   float_value
• %if      <=====>   double_value
• %c      <=====>   Character_value