Windows操作系統(tǒng)下如何使用EOF#include <stdio.h>int main(){?char grade;?int? A_num, B_num, C_num, D_num;?//定義變量 ?A_num=0;?B_num=0;?C_num=0;????//初始化變量 ?D_num=0;??printf("請輸入所有人的成績："); ?while ((grade=getchar())!=-1)?{??switch (grade)??{???case 'A':???case 'a': ????A_num=A_num+1;????break; ???case 'B':???case 'b':????B_num=B_num+1;????break;???case 'C':???case 'c':????C_num=C_num+1;????break;???case 'D':???case 'd':????D_num=D_num+1;????break;???default:????printf("\n"); ??????}?}?printf("A有 %d 人\n\B有 %d 人\n\C有 %d 人\n\D有 %d 人\n",A_num,B_num,C_num,D_num); ?}