# [Python] Checkio Solution 解答 – Secret Message

Ever tried to send a secret message to someone without using the postal service? You could use newspapers to tell your secret. Even if someone finds your message, it's easy to brush them off and that its paranoia and a bogus conspiracy theory. One of the simplest ways to hide a secret message is to use capital letters. Let's find some of these secret messages.

# [Python] Checkio Solution 解答 – Three Words

Let's teach the Robots to distinguish words and numbers.

# [Python] Checkio Solution 解答 – Index Power

You are given an array with positive numbers and a number N. You should find the N-th power of the element in the array with the index N. If N is outside of the array, then return -1. Don't forget that the first element has the index 0.

# [Python] Checkio Solution 解答 – Fizz Buzz

"Fizz buzz" is a word game we will use to teach the robots about division. Let's learn computers.

# [Python] Checkio Solution 解答 – Long Repeat

This mission is the first one of the series. Here you should find the length of the longest substring that consists of the same letter. For example, line "aaabbcaaaa" contains four substrings with the same letters "aaa", "bb","c" and "aaaa". The last substring is the longest one which makes it an answer.

# [Python] Checkio Solution 解答 – Monkey Typing

The infinite monkey theorem states that a monkey hitting keys at random on a typewriter keyboard for an infinite length of time will almost surely type out a given text, such as the complete works of John Wallis, or more likely, a Dan Brown novel.

# [Python] Checkio Solution 解答 – House Password

Stephan and Sophia forget about security and use simple passwords for everything. Help Nikola develop a password security check module. The password will be considered strong enough if its length is greater than or equal to 10 symbols, it has at least one digit, as well as containing one uppercase letter and one lowercase letter in it. The password contains only ASCII latin letters or digits.

# [Python] Checkio Solution 解答 – Non-Unique Elements

You are given a non-empty list of integers (X). For this task, you should return a list consisting of only the non-unique elements in this list. To do so you will need to remove all unique elements (elements which are contained in a given list only once). When solving this task, do not change the order of the list. Example: [1, 2, 3, 1, 3] 1 and 3 non-unique elements and result will be [1, 3, 1, 3].

# [Python] Checkio Solution 解答 - The Most Wanted Letter

You are given a text, which contains different english letters and punctuation symbols. You should find the most frequent letter in the text. The letter returned must be in lower case.
While checking for the most wanted letter, casing does not matter, so for the purpose of your search, "A" == "a". Make sure you do not count punctuation symbols, digits and whitespaces, only letters.