3974: Punctuation
Description
You are given a text that consists of lowercase Latin letters, spaces and punctuation marks (dot, comma, exclamation mark and question mark). A word is defined as a sequence of consecutive Latin letters.
Your task is to add spaces to the text by the following rules:
- if there is no punctuation mark between two words, then they should be separated by exactly one space
- there should be no spaces before each punctuation mark
- there should be exactly one space after each punctuation mark
It is guaranteed that there is at least one word between any two punctuation marks. The text begins and ends with a Latin letter.
The input data contains of a single non-empty line − the text whose length is no more than 10000 characters.
Print the text, edited according to the rules. In this problem you should follow the output format very strictly. For example, extra space at the end of the output line is considered as wrong answer. Note that a newline character at the end of the line doesn't matter.
galileo galilei was an italian physicist ,mathematician,astronomer
galileo galilei was an italian physicist, mathematician, astronomer
galileo was born in pisa
galileo was born in pisa