1. If arr represents an array, suppose that arr++ was used in an expression. Under what circumstances would its use be illegal? Under what circumstances would its use be legal? When it is legal, what does it mean? (You can assume that the expression is itself legal and correctly placed in the program.)
2. Here is a structure definition:
struct studentInfo
{
string lastName, firstName;
int *ID; // pointer
double gpa;
};
a) Declare a vector of these structures where the size of the vector is to be 7.
b) Put data into the last struct of the vector for each of the members of the struct.
if you could give informative answers that would help a lot. thank you