Objective

Write free_str_array, which releases every string of a NULL-terminated char **, then releases the array of pointers itself, and returns how many strings it held.

Steps

• arr points to an array of char *. Every string it holds came from malloc, and so did the array of pointers.
• A NULL pointer marks the end of the array. That slot is not a string: nothing frees it, and it never counts.
• Walk from index 0 to the NULL slot and free each string on the way.
• Free arr itself once the last string is gone. The order is not a style preference: free(arr) first releases the only place those string pointers were stored, and every string becomes unreachable for the rest of the process.
• Return the number of strings freed. An array whose very first slot is NULL held zero strings.
• An arr of NULL is a legal call. Return 0 and free nothing.
• An empty string is a string. A char * pointing at a lone '\0' byte came from malloc like any other and counts like any other.
• Grademe allocates the array and each of its strings before every call, then hands ownership to your function and never reads arr again. Each test is replayed under a memory checker and that cell is the real verdict: the returned count can be correct while the memory cell goes red because one string was skipped or the array of pointers was left behind.

Objective

Write free_str_array, which releases every string of a NULL-terminated char **, then releases the array of pointers itself, and returns how many strings it held.

Steps

• arr points to an array of char *. Every string it holds came from malloc, and so did the array of pointers.
• A NULL pointer marks the end of the array. That slot is not a string: nothing frees it, and it never counts.
• Walk from index 0 to the NULL slot and free each string on the way.
• Free arr itself once the last string is gone. The order is not a style preference: free(arr) first releases the only place those string pointers were stored, and every string becomes unreachable for the rest of the process.
• Return the number of strings freed. An array whose very first slot is NULL held zero strings.
• An arr of NULL is a legal call. Return 0 and free nothing.
• An empty string is a string. A char * pointing at a lone '\0' byte came from malloc like any other and counts like any other.
• Grademe allocates the array and each of its strings before every call, then hands ownership to your function and never reads arr again. Each test is replayed under a memory checker and that cell is the real verdict: the returned count can be correct while the memory cell goes red because one string was skipped or the array of pointers was left behind.