IOS junior programmer face test const keyword

  ios, question

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Please help me answer it. Mainly 3 4 5

I am also just getting started. Let’s talk about it:

Like 2, int constant is read-only after initialization.
 3 means pointer a is variable, (*a) is read-only, a can point to different int variables, (*a) is read-only, for example (*a)=1 cannot be compiled.
 4 means pointer a is read-only, (*a) is variable. once a is initialized and points to a variable, it is not allowed to change, but (*a)=1 is allowed.
 5 means pointers a and (*a) are both read-only.