#include<stdio.h> int main() { char num; while(scanf("%c",&num)==1) { if((num>=65)&&(num<=90)) { num=num+32; printf("%c\n",num); } else if((num>=97)&&(num<=122)) { num=num-32; printf("%c\n",num); } else { ; } } return 0; }
原文:http://10740329.blog.51cto.com/10730329/1698975