C语言学习(9)

 1 #include <stdio.h>
 2 #include <string.h>
 3 int main(){
 4     char s[100];
 5     gets(s);
 6     printf("原字符串:%s\n",s);
 7     printf("变大写字符串%s\n",strupr(s));
 8     printf("变小写字符串%s\n",strlwr(s));
 9     return 0;
10 }