Question

Switch语句括号中的值可不可以是null，case值可不可以是null

Answer 1

不能。只能用多个值用同一块执行代码。比如

switch( make/5){
case 18: case 19: case 20: printf("A");break;
case 16: case 17: printf("B");break;
case 14: case 15: printf("C");break;
case 12: case 13: printf("D");break;
default: printf("E");break;
}