Step 5 of 10

null

NULL is a special pointer value meaning "points at nothing". Dereferencing NULL crashes the program (on a normal OS it's the famous segmentation fault).

Always check a pointer that might be NULL before using it:

if (p != NULL) {
    printf("%d\n", *p);
}

Your turn: write int safe_get(const int *p, int fallback) that returns *p, or fallback if p is NULL.

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