A. Genetic Discovery
time limit per test
1 second
memory limit per test
256 megabytes
input
standard input
output
standard output

Darwin has discovered a rare new species of tortoises! He and his team of scientists have several different sites where they extracted DNA from tortoise remains. However, at each site, some of the nucleotide pairs are missing, and they need your help putting it back together.

We represent DNA strands as a string of nucleotides (letters 'A', 'T', 'G', 'C'); Darwin has some number of these strands. However, parts of it may be missing, denoted by the '.' character. Help Darwin reconstruct the most complete version of the DNA sequence as he can!

Input

The first line contains a single integer $$$n$$$ ($$$1 \le n \le 100$$$) denoting the number of DNA strands. On each of the next $$$n$$$ lines is a string $$$s$$$ ($$$1 \le |s| \le 100$$$) consisting of the characters 'A', 'T', 'G', 'C', and '.'.

All strings are guaranteed to be the same length. Additionally, we guarantee that for all pairs of strings and for each index $$$i$$$, either both strings have the same character at index $$$i$$$, or at least one string has the '.' character at index $$$i$$$.

Output

Output a single line denoting the most complete sequence (the least '.' possible) that is consistent with all sequences in the input.

Examples
Input
3
.ATTACAGC
AAT..CAGC
AATTAC...
Output
AATTACAGC
Input
3
...T
..TT
G...
Output
G.TT
Note

In the first example, the most complete sequence is 'AATTACAGC'.

In the second example, the most complete sequence is 'G.TT'.