Find substrings containing an e$-$mail address

Cost: $8|$ Solved: $9$

Memory limit: $256$ Mb

Time limit: $1000$ ms

Input file: stdin

Output file: stdout Input:

A set of strings separated with line feed characters.

Output:

All the longest correct substrings in the order in which they appear in the text, separating each with a line feed character.

$**$ Use only C$++**$