int n;
int *variable = scanf("%d",&n);
printf("Printing :%d",*variable);

int n;
scanf("%d",&n);
int *variable = &n;
printf("Printing :%d",*variable);

int scanf(const char *format, ...);

int *variable = scanf("%d",&n);

*variable

int n;
int *variable = &(scanf("%d",&n), n);

void foo(void)
{
   int a;
   int *b = &a;     //you assign the pointer `b` itself - no dereferencing

   *b = 5;          //you dereference the pointer and asssign the the referenced object
}

void foo(void)
{
   int a;
   int *b = &a;     //b is pointing to the valid object -> the variable `a`
   int *c;     //c is not pointing to valid object
   int *d;     //d is not pointing to valid object

   c = malloc(sizeof(*c));     //now c is pointing to the valid object (if malloc has not failed of course)
   *c = 5      // correct no UB
   *d = 5;         // incorrect - UB


   *b = 5;          //correct no UB
}