Scanf In C

Scanf In C

In C programming, scanf is a function used to read data from the standard input (typically the keyboard) and store the result in specified variables. It can handle character, string, and numeric input and utilizes format specifiers similar to printf.

Scanf Syntax

The syntax of scanf() in C is similar to the syntax of printf()

int scanf( const char *format, ... );

• Return Type: int is the return type, indicating that printf returns an integer value, typically denoting the number of characters printed.
• Format String: “format” is a string that contains format specifiers, allowing you to control the formatting of the output.
• “…” (ellipsis): The ellipsis (…) indicates that printf can accept a variable number of arguments, corresponding to the format specifiers in the format string. This flexibility allows you to print multiple values of different types in a single printf statement

Example format specifiers recognized by scanf:

%d to accept input of integers.

%ld to  accept input of long integers

%lld to accept input of long long integers

%f to accept input of real number.

%c to accept input of character types.

%s to accept input of a string.

Example

int var;
scanf(“%d”, &var);

Return Value of scanf

• Greater than 0: This indicates that the number of values converted and assigned successfully. It means that scanf successfully read and assigned data according to the provided format specifiers.
• Equal to 0: This means that no value was assigned. It typically occurs when scanf couldn’t match the input with the specified format, or when no input was provided.
• Less than 0: This indicates a read error encountered or that the end-of-file (EOF) was reached before any assignment was made. It suggests a problem with reading input, such as reaching the end of a file or encountering an error while reading.

Why &?

• The ampersand (&) operator is often referred to as the “address of” operator.
• It is used to obtain the memory address of a variable.
• For example, &var represents the address of the variable var.

Example Of Scanf

C Program to implement Scanf

// C program to implement
// scanf
#include <stdio.h>
 
// Driver code
int main()
{
    int a, b;
   
      printf("Enter first number: ");
      scanf("%d", &a);
   
      printf("Enter second number: ");
      scanf("%d", &b);
   
      printf("A : %d \t B : %d" ,
            a , b);
   
    return 0;
}

Output

Enter first number: 5
Enter second number: 6
A : 5      B : 6

FAQ- Scanf In C