This program will input chars in text mode, one char at a time, from a file named "input", and

will output chars, one char at a time, to a file named "output".

Try to open "input", c&d on failure. (text mode, for reading)

Try to open "output, c&d on failure. (text mode, for writing)

Your program may awc that if the files open without error, then there will be no error in reading or

writing (not counting the inevitable end-of-file for the input).

For every character read from "input", write that character twice to output unless the character is

, in which case write it only once.

For example, if input consisted of 2 lines:

first line

second line

Then output would also consist of 2 lines:

ffiirrsstt lliinnee

sseeccoonndd lliinnee