Bitfields in C: solved exercise for compact flags

Bitfields in C: solved exercise for compact flags

This exercise is scheduled for daily publication and follows the same didactic structure used across the site: clear statement, compilable code, and expected output.

Problem statement

Implement a practical example of the topic and validate the output in the console.

C solution

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#include <stdio.h>

typedef struct {
    unsigned int lectura : 1;
    unsigned int escritura : 1;
    unsigned int ejecucion : 1;
} Permisos;

int main(void) {
    Permisos p = {1, 0, 1};
    printf("R:%u W:%u X:%u\n", p.lectura, p.escritura, p.ejecucion);
    return 0;
}

Expected output

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R:1 W:0 X:1

Common mistakes

  • Not validating input and standard-library return values.
  • Ignoring edge cases (buffers, limits, null pointers).
  • Skipping basic compile/run verification.

Practical use

Bit fields are used in network protocols, embedded hardware registers, and compact data formats.

Guided practice and full book

If you want a complete path with progressive difficulty:

FAQ

Is this exercise useful for C exams and technical interviews?

Yes. It targets patterns that commonly appear in practice assignments, technical interviews, and C programming exams.

Where can I keep practicing with more solved C exercises?

In Programming in C in 100 Solved Exercises and C Exercises. Kindle Unlimited: View on Amazon.

How should I practice this exercise type to improve faster?

Start with small inputs, run edge cases (empty, one item, max capacity), then rewrite the solution from scratch without copying.