Is it possible to get a pointer to a full element of an object representation from a pointer to a subproject?

Question

Consider this code:

int i;
int is[10]{};

unsigned char * p = reinterpret_cast<unsigned char*>(&i);
//p defined to point to the object-representation of the first element of array ints
unsigned char * ps = reinterpret_cast<unsigned char*>(&is[0]);

p += sizeof(int);
ps += sizeof(int);
//now ps points to the end of ints[0] and p point to the end of i;

p += sizeof(int); //Undefined behavior according to [expr.add]

ps += sizeof(int); //Undefined behavior?
unsigned char c = *ps;//Undefined behavior?

If we believe that it pspoints to a representation object is[0] , then according to the arithmetic rule of the pointer, the behavior is undefined in the last two lines of code.

However, if psit is also a pointer to an int array representation object is, then the behavior is determined.

So my question is: is a pointer to an object representing an object also a pointer to an element of an object representing a complete object?

Answer 1

General case

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, 2 undefined, is

Answer 2

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