編寫程序，輸入一個數(shù)字字符，輸出其前一個和后一個的數(shù)字字符，如果輸入的是0前一個輸出 “first”，9后一個則輸出“l(fā)ast”，輸入的不是數(shù)學(xué)字符，輸出“error”#include?<stdio.h> #include?<stdlib.h>int?main() {??? char?a;???a=getchar();??? ?switch(a)??? ?{???????case?'0':printf("frist?1");break;?????? ??case?'1':printf("0?2");break;??????? ??case?'2':printf("1?3");break;??????? ??case?'3':printf("2?4");break;?????? ???case?'4':printf("3?5");break;??????? ???case?'5':printf("4?6");break;??????? ???case?'6':printf("5?7");break;?????? ????case?'7':printf("6?8");break;??????? ????case?'8':printf("7?9");break;??????? ????case?'9':printf("8?last");break;??????? ????default:???????printf("error");???} ????}