指向包含vector issue的实例类的指针

class largeInt{
  vector<int> myVector;
  largeInt  operator*  (const largeInt &arg);

}

void main(){

    //this works but there are multiple copies: I return a copy of the calculated
    //largeInt from the multiplication and then i create a new largeInt from that copy.
    largeInt testNum = 10;
    largeInt *pNum = new HugeInt( testNum*10);

    //i think this code avoid one copy but at the end hI points to a largeInt that has
    // myVector = 0 (seems to be a new instance = 0 ). With simple ints this works  great.
    largeInt i = 10;
    largeInt *hI;
    hI = &(i*10);

}

hI = &(i*10);

hI

largeInt

int L = 3, R = 5;

int j = L*R; // You *want* a new instance - L and R shouldn\'t change
L*=R; // You don\'t want a new instance - L is modified, R is unchanged

new

largeInt i = 10; 
largeInt hi = i*10; // Create a temporary, copy construct from the temporary

largeInt i = 10;
largeInt hi = i; // Copy construction
hi *= 10; // Modify hi directly