Pointer subtraction confusion

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The idea is that you’re pointing to blocks of memory

+----+----+----+----+----+----+
| 06 | 07 | 08 | 09 | 10 | 11 | mem
+----+----+----+----+----+----+
| 18 | 24 | 17 | 53 | -7 | 14 | data
+----+----+----+----+----+----+

If you have int* p = &(array[5]) then *p will be 14. Going p=p-3 would make *p be 17.

So if you have int* p = &(array[5]) and int *q = &(array[3]), then p-q should be 2, because the pointers are point to memory that are 2 blocks apart.

When dealing with raw memory (arrays, lists, maps, etc) draw lots of boxes! It really helps!

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