C/C++黑魔法-另类switch

int n = 1;switch (n) {    case 0: do { printf("%d ", 0);    case 1: printf("%d ", 1);    case 2: printf("%d ", 2);    case 3: printf("%d ", 3);    case 4: printf("%d ", 4);            } while (n-- > 0);}

1 2 3 4 0 1 2 3 4 

int i = 5;switch (i) {    case 0 ... 3:        std::cout<<"0-3: "<<i<<std::endl;        break;    case 4 ... 6:        std::cout<<"4-6: "<<i<<std::endl;        break;    case 7 ... 9:        std::cout<<"7-9: "<<i<<std::endl;        break;    case 10:        std::cout<<"10"<<i<<std::endl;    default:        break;}

4-6: 5