pointer and quote

example 1:

int a = 5;
int *b = &a;

note: get the memory address of a, and store it in an int point b. &b == a == 5.


example 2:

void swap(int *x, int *y){    // normal pointer usage.
      int temp = *x;
      *x = *y;
      *y = temp;
}

void swap(int &x, int &y){    // quote here means use a different name and same memory.
      int temp = x;
      x = y;
      y = temp;
}