Difference between dereferencing pointer and accessing array elements

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Thanks to the link provided by @tesseract in the comments: Expert C Programming: Deep C Secrets (page 96), I came up with a simple answer (a simple dumb down version of the explanation in the book; for a full academic answer read the book):

  • when declared int a[2]:
    • the compiler has for a an address where this variable is stored. This address is also the address of the array since the type of the variable is array.
    • Accessing a[1] means:
      • retrieving that address,
      • adding the offset and
      • accessing the memory at this computed new address.
  • when declared int *b:
    • the compiler also has an address for b but this is the address of the pointer variable, not the array.
    • So accessing b[1] means:
      • retrieving that address,
      • accessing that location to get the value of b, i.e. the address of the array
      • adding an offset to this address and then
      • accessing the final memory location.

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