Andy's First Dictionary#1227
Andy dreams of creating his own dictionary. However, this is not an easy task, as he knows only a limited number of words. Instead of recalling all the words himself, Andy has a brilliant idea. He decides to take his favorite book from the shelf and copy out all distinct words from it. Then he arranges all the words in alphabetical order. Of course, this is a time-consuming job, so he needs a computer program.
You are asked to write a program that lists all the different words in the input text. In this problem, a word is defined as a sequence of upper or lower case Latin letters. Words with only one letter should also be considered. The program must be case-insensitive: for example, "Apple", "apple", and "APPLE" are considered the same word.
The input contains text with no more than lines. Each line contains at most characters.
Output the list of different words found in the text, one word per line. The words should contain only lower case letters and be sorted in alphabetical order. The number of distinct words in the input does not exceed .
Example 1