例8-3swap3()swap3(&a,&b);void swap3 (int *px, int *py) int*pt;pt = px;After calling swap1:a=1, b=2px = py;After calling swap2: a=2, b=1py = pt;After calling swap3: a=1, b=21例8-3 swap3() swap3 (&a, &b); void swap3 (int *px, int *py) { int *pt; pt = px; px = py; py = pt; } After calling swap1: a=1, b=2 After calling swap2: a=2, b=1 After calling swap3: a=1, b=2