将字符串的小写字母转换为大写字母

void fun( char *str )
{
    
  int len ;
  len = strlen(str);
  char *p = str;
  //char *dest=(char*)malloc(len);

   while(*p != '\0')
  {    
       if( *p>='a'&&*p<='z' ) //小写字符
      {
                 *p = *p -('a'-'A');
      }
            p++;
  }
  cout<<str<<endl;
}

void main()
{
 char str[]="ABcdEFgh";
 fun(str);
}