TORONTO KIDS COMPUTER CLUB | Aurora Saturday 14:30 Python Practice 21.05.08.
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# Aurora Saturday 14:30 Python Practice 21.05.08.

## 11 May Aurora Saturday 14:30 Python Practice 21.05.08.

Question 1:
Numerous local and international recreational runners were eager to take part in this year’s Zagreb Marathon! It is an already traditional race 42125 meters long. A curious statistical info is that this year every single contestant managed to complete the race, except one.

Since marathons are all about taking part, help the organizers figure out, based on the list of registered contestants and ranking list, the identity of the contestant that did not complete the race.

Input Specification
The first line of input contains the integer N (1≤N≤100000), the number of contestants.
Each of the following N lines contains the names of registered contestants.
The additional N−1 lines contain the names of contestants in the order which they completed the race.

The contestants’ names will consist of at least one and at most twenty lowercase letters of the English alphabet.

The contestants’ names won’t necessarily be unique.

Output Specification
The first and only line of output must contain the name of the contestant who didn’t finish the race.

Sample Input 1
3
leo
kiki
eden
eden
kiki

Sample Output 1
leo

Sample Input 2
5
marina
josipa
nikola
vinko
filipa
josipa
filipa
marina
nikola

Sample Output 2
vinko

Sample Input 3
4
mislav
stanko
mislav
ana
stanko
ana
mislav

Sample Output 3
mislav

Question 2:

Little Marin spent all his day generating test data for COCI. He simply couldn’t make it work, so he had a nervous breakdown and can’t even see clearly anymore. Every time he blinks while reading, the letters in a word get mixed up so that the letters from the second half of the word (the shorter half, if the length is an odd number) “jump in” between the letters from the first half in the following way:

• the last letter “jumps in” between the first and the second letter
• the penultimate letter “jumps in” between the second and the third letter
• the kth letter from the end “jumps in” between the kth and the (k+1)th letter from the beginning

For example, the word abcdef would become afbecd after blinking.

If Marin blinks again, the same thing happens. After two blinks, the word abcdef becomes adfcbe.

Marin has decided to write a program to help him determine what’s exactly written on the screen. Unfortunately, after a day’s work, he’s simply too tired and he needs your help. You are given X, the number of blinks, and the word Marin sees on the screen. Write a program to solve the mystery for Marin and determine what was actually the word before he blinked X times.

#### Input

The first line of input contains a positive integer X (1X1000000000), the number of times Marin blinked.

The second line of input contains the word from the screen, its length being from the interval [3,1000].

The word will consist only from small letters of English alphabet.

#### Output

The first and only line of output must contain the original word, before Marin blinked X times.

Sample Input 1
4
acefdb

Sample Output 1
abcdef

Explanation for Sample Output 1
The word gets altered in the following order:

Sample Input 2
1000
aaaaaa

Sample Output 2
aaaaaa

Sample Input 3
11
srama

Sample Output 3
sarma