实验二task3

include <stdio.h>

int main() {
char input;

while (1) {
    input = getchar();
    while (getchar() != '\n');
    switch (input) {
    case 'r':
    case 'R':
        printf("stop!\n");
        break;
    case 'g':
    case 'G':
        printf("go go go\n");
        break;
    case 'y':
    case 'Y':
        printf("wait a minute\n");
        break;
    case EOF: 
        printf("\n程序已终止。\n");
        return 0;
    default:
        printf("something must be wrong...\n");
        break;
    }
}

return 0;

}