How to Take Hexadecimal Input in C Using scanf()

#include <stdio.h>
#include <stdio.h>
int main()
{
int hexValue;

// Ask the user to enter a hexadecimal number
printf("Enter a hexadecimal number (e.g., 0x1A or 1A): ");
scanf("%x", &hexValue); // %x reads hex input

// Display the value in decimal format
printf("You entered: %d (decimal)\n", hexValue);
return 0;
}

Output:
Enter a hexadecimal number (e.g., 0x1A or 1A): 1F
You entered: 31 (decimal)

Description:
Taking hexadecimal input from users in C might sound tricky at first, but it's actually very straightforward. In this beginner-friendly walkthrough you'll learn how to use scanf() to accept a hex number and display its decimal equivalent.
Let’s walk through it step by step:

Step 1: Include the necessary library
#include <stdio.h>
This gives access to the printf() and scanf() functions used for input and output.

Step 2: Start your program with main()
int main() {
This is where your program begins. Every C program starts here.

Step 3: Declare a variable to hold the hex input
int hexValue;
We’ll store the number the user enters in this variable. Even though it’s typed in as hexadecimal, it’ll be stored as a normal integer.

Step 4: Ask the user to enter a hex number
printf("Enter a hexadecimal number (like 0x1A): ");
scanf("%x", &hexValue);
The %x format specifier tells scanf() to treat the input as hexadecimal. It works whether the user types 0x1F, 0X2A, or just 1A.

Step 5: Display the result in decimal format
printf("You entered: %d (decimal)\n", hexValue);
This prints out the decimal equivalent of the hex number. It's an easy way to confirm that the input worked correctly.

Step 6: End the program
return 0;
}
This just tells the system the program ran successfully.

Example Output
Enter a hexadecimal number (like 0x1A): 1F
You entered: 31 (decimal)

Accepting Hexadecimal Input in C Using scanf() Step by Step for Beginners

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