include<stdio.h>#include<ctype.h>int main(void){char gothere = 0;while(1){printf("\ninput y continue,input n over.\n");scanf("%c",&gothere);getchar(); //消除回车键，回车键也是一个字符，如果不消除下次默认输入回车键if(!isalpha(gothere)){printf("error ,retry");}else...