Arithmetic Progression

One day Petya found a very important sequence of $n$ numbers. After a careful analysis, he determined that it is an arithmetic progression. So he would not forget it, he wrote its elements on $n$ cards.

Then an accident happened. Not knowing how important the sequence was, his brother Vovochka took $n$ more cards, wrote arbitrary numbers on them, and shuffled all $2n$ cards together.

Now Petya wants to restore the original sequence from these cards. It may be possible to do this in several ways, but Petya is satisfied with any $n$ numbers that form an arithmetic progression.

Petya cannot do this by hand, so he asked you for help.

The first line contains an integer $n$ ($1 \le n \le 100\,000$). The next line contains $2n$ integers whose absolute values do not exceed $10^9$, the numbers written on the cards, listed in arbitrary order. It is guaranteed that you can choose $n$ of them that form an arithmetic progression.

Print $a_1$ and $d$ on the first line, the first element and the difference of the found arithmetic progression. If $d = 0$, the number $a_1$ must appear among the given numbers $n$ times.

If there are several solutions, print any of them.