#include #include void main(){int i,n;char str[80]={'\0'};gets(str);n=strlen(str);for(i=0;iif(str[i]>='A'&&str[i]<='Z')str[i]='A'+(str[i]+5-'A')%26;else if(str[i]>='a'&&str[i]<='z')str[i]='a'+(str[i]+5-'a')%26;printf("%s",str);}
运行示例：
#include int main(){char tmp;scanf("%c" , &tmp);if( tmp >= 65 && tmp <= 90) //大写转换小写{tmp = tmp + 32;printf("%c" , tmp);return 0;}if( tmp >=97 && tmp <= 122) //小写转换大写{tmp =tmp - 32;printf("%c" , tmp);return 0;}}
