Delete a pointer after the arithmetics

Question

int main() {
  int* i = new int(1);
  i++;
  *i=1;
  delete i;
}

Here is my logic:

I increment I by 1, and then assign a value to it. Then

Answer 1

Let's take it step by step:

int* i = new int(1);  // 1. Allocate a memory.
i++;                  // 2. Increment a pointer. The pointer now points to
                      //    another location.
*i=1;                 // 3. Dereference a pointer which points to unknown
                      //    memory. This could cause segmentation fault.
delete i;             // 4. Delete the unknown memory which is undefined 
                      //    behavior.

In short: If you don't own a piece of memory you can't do arithmetic with it neither delete it!