Linguagem C - Aula 2.2 - Inserindo dados pelo teclado em C - scanf - entrada de dados (2022)

Introduction

This tutorial provides a step-by-step guide on how to use the scanf function in the C programming language for reading input from the keyboard. Understanding how to capture user input is essential for interactive programs and enhances your ability to create dynamic applications.

Step 1: Setting Up Your Environment

Before you can use scanf, ensure you have a suitable environment to write and run your C code.

• Install a C compiler (e.g., GCC).
• Use a code editor or an Integrated Development Environment (IDE) such as Code::Blocks or Visual Studio Code.

Step 2: Writing Your First Program

Start by creating a simple C program to demonstrate the scanf function.

1. Open your code editor and create a new file named input_example.c.
2. Start with the basic structure of a C program:

#include <stdio.h>

int main() {
    // Your code will go here
    return 0;
}

Step 3: Using scanf to Capture Input

Now, let's add code to capture user input using scanf.

1. Inside the main function, declare a variable to hold the user's input. For example, if you want to capture an integer:

int number;

2. Use the scanf function to read input from the user:

printf("Enter an integer: ");
scanf("%d", &number);

3. The complete code should look like this:

#include <stdio.h>

int main() {
    int number;
    printf("Enter an integer: ");
    scanf("%d", &number);
    printf("You entered: %d\n", number);
    return 0;
}

Step 4: Compiling and Running Your Program

To see your program in action, follow these steps:

1. Open your terminal or command prompt.
2. Navigate to the directory where your input_example.c file is located.
3. Compile your program using the following command:

gcc input_example.c -o input_example

4. Run your program:

./input_example

5. Enter an integer when prompted. The program should display the integer you entered.

Step 5: Handling Different Data Types

You can use scanf to read different types of data, such as floats or strings. Here’s how:

• For a float:

float decimal;
printf("Enter a decimal number: ");
scanf("%f", &decimal);

• For a string (character array):

char name[50];
printf("Enter your name: ");
scanf("%s", name);

Conclusion

You've learned how to use the scanf function in C to capture user input from the keyboard. Key takeaways include:

• Setting up your programming environment.
• Writing a basic C program that uses scanf.
• Compiling and executing your code.
• Capturing different types of input.

Next, consider practicing by creating programs that handle multiple inputs or perform calculations based on user input. Happy coding!