int deref_and_store(int *p) {
*p = 42; /* faults here when p == NULL */
return *p;
}
int main(void) {
int *p = 0; /* null pointer */
return deref_and_store(p);
}A lab is done when you can say what it showed on your machine — not when you have read it.
It decides which problems come first, which drills open, which labs you see and how the Learn surface is organised. Change it any time from the switch in the top bar, or press Escape to look around first.