const in C: solved exercise with read-only parameters

const in C: solved exercise with read-only parameters

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>

int suma_array(const int a[], int n) {
    int suma = 0;
    for (int i = 0; i < n; i++) suma += a[i];
    return suma;
}

int main(void) {
    const int datos[] = {2, 4, 6, 8};
    int n = (int)(sizeof(datos) / sizeof(datos[0]));
    printf("Suma = %d\n", suma_array(datos, n));
    return 0;
}

Expected output

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Suma = 20

Common mistakes

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

Practical use

The const qualifier is used to define symbolic constants and protect function parameters that must not be modified.

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.