问答题
#include "string.h" main() {char s[81]; int i=0; gets(s); while(s[i]!='\0') {if(s[i]＞='a'&&s[i]＜='z')s[i]=s[i]-3; if(s[i]＞'A'&&s[i]＜='Z')s[i]=s[i]+3; i++; } puts(s); }