Lists

Write a function that remove duplicates from a list: for example:

[1, 3, 5, 3, 7, 3, 1, 1, 5]

should return

[1, 3, 5, 7]

Write a function that count each elements in a list: for example:

[1, 3, 5, 3, 7, 3, 1, 1, 5]

should become

{
  1: 3,
  3: 3,
  5: 2,
  7: 1
}

Run-Length Encoding

Run-Length Encoding is a simple compression scheme. You replace consecutive occurence of the same later by the number of time it appears followed by the letter. You can suppose the string will only have letter from A to Z.

Example:

WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW

is compressed to:

12W1B12W3B24W1B14W

Run-Length Decoding

Write the function to decode results from previous exercise:

12W1B12W3B24W1B14W

should give:

WWWWWWWWWWWWBWWWWWWWWWWWWBBBWWWWWWWWWWWWWWWWWWWWWWWWBWWWWWWWWWWWWWW

FizzBuzz

Write a fizzbuzz function that takes no parameter as input and print in the console the numbers from 1 to 100 and replace the number by:

Fizz if it is divisible by 3
Buzz if it is divisible by 5
FizzBuzz if it is divisible by both

The beginning of the output should be:

1
2
Fizz
4
Buzz
Fizz
7
8
Fizz
Buzz
11
Fizz
13
14
FizzBuzz
16

Dictionnary changes

Write a function replace_dashes that takes a dictionnary as input and rename the keys so that every '_' is replaced by '-'. Your function should not change the values, for example, if the input is:

{
  "key_1": "value_1",
  "key_2": "value_2",
  "key_3": {
    "key_4": "value_4"
  }
}

its output should be:

{
  "key-1": "value_1",
  "key-2": "value_2",
  "key-3": {
    "key-4": "value_4"
  }
}

You can suppose that the input will be a valid JSON object.

Counting

Write a program that outputs all possibilities to put + or - or nothing between the numbers 1,2,…,9 (in this order) such that the result is 100. For example

1 + 2 + 3 - 4 + 5 + 6 + 78 + 9 = 100