Output

Output all the email addresses, one per line, that appears in the text, by the order of their appearances. Assume email addresses are in this format:

• Each address is on a single line only. A line can contain several addresses.
• Each address consists of two parts, the user name, and the domain name. They are separated by @. Names have at least one characters.
• Valid characters are the alphabets (A to Z, lower or upper cases) numbers (0 to 9) and underscores _.
• Periods (.) can be used in both user name and the domain name. For example, John.Doe@dummy.com is a valid address. A period must be surrounded by two words, so john.doe.@dummy, john..doe@dummy, etc. are not valid email addresses.

Once a part of a line is determined to be an email address, that part of the line would not be considered again. Scanning starts at the beginning of the line. For example, for the line:

a@b@c@d@e

after a@b is determined to be an email address, only the part @c@d@e would be considered subsequently. So the valid email addresses on this line are a@b and c@d only.