Added 2017

2017/01/1.md

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+## \-\-- Day 1: Inverse Captcha \-\--
+
+The night before Christmas, one of Santa\'s Elves calls you in a panic.
+\"The printer\'s broken! We can\'t print the *Naughty or Nice List*!\"
+By the time you make it to [sub-basement
+17]{title="Floor 17: cafeteria, printing department, and experimental organic digitization equipment."},
+there are only a few minutes until midnight. \"We have a big problem,\"
+she says; \"there must be almost *fifty* bugs in this system, but
+nothing else can print The List. Stand in this square, quick! There\'s
+no time to explain; if you can convince them to pay you in *stars*,
+you\'ll be able to\--\" She pulls a lever and the world goes blurry.
+
+When your eyes can focus again, everything seems a lot more pixelated
+than before. She must have sent you inside the computer! You check the
+system clock: *25 milliseconds* until midnight. With that much time, you
+should be able to collect all *fifty stars* by December 25th.
+
+Collect stars by solving puzzles. Two puzzles will be made available on
+each ~~day~~ millisecond in the Advent calendar; the second puzzle is
+unlocked when you complete the first. Each puzzle grants *one star*.
+Good luck!
+
+You\'re standing in a room with \"digitization quarantine\" written in
+LEDs along one wall. The only door is locked, but it includes a small
+interface. \"Restricted Area - Strictly No Digitized Users Allowed.\"
+
+It goes on to explain that you may only leave by solving a
+[captcha](https://en.wikipedia.org/wiki/CAPTCHA) to prove you\'re *not*
+a human. Apparently, you only get one millisecond to solve the captcha:
+too fast for a normal human, but it feels like hours to you.
+
+The captcha requires you to review a sequence of digits (your puzzle
+input) and find the *sum* of all digits that match the *next* digit in
+the list. The list is circular, so the digit after the last digit is the
+*first* digit in the list.
+
+For example:
+
+-   `1122` produces a sum of `3` (`1` + `2`) because the first digit
+    (`1`) matches the second digit and the third digit (`2`) matches the
+    fourth digit.
+-   `1111` produces `4` because each digit (all `1`) matches the next.
+-   `1234` produces `0` because no digit matches the next.
+-   `91212129` produces `9` because the only digit that matches the next
+    one is the last digit, `9`.
+
+*What is the solution* to your captcha?
+
+Your puzzle answer was `1158`.
+
+## \-\-- Part Two \-\-- {#part2}
+
+You notice a progress bar that jumps to 50% completion. Apparently, the
+door isn\'t yet satisfied, but it did emit a *star* as encouragement.
+The instructions change:
+
+Now, instead of considering the *next* digit, it wants you to consider
+the digit *halfway around* the circular list. That is, if your list
+contains `10` items, only include a digit in your sum if the digit
+`10/2 = 5` steps forward matches it. Fortunately, your list has an even
+number of elements.
+
+For example:
+
+-   `1212` produces `6`: the list contains `4` items, and all four
+    digits match the digit `2` items ahead.
+-   `1221` produces `0`, because every comparison is between a `1` and a
+    `2`.
+-   `123425` produces `4`, because both `2`s match each other, but no
+    other digit has a match.
+-   `123123` produces `12`.
+-   `12131415` produces `4`.
+
+*What is the solution* to your new captcha?
+
+Your puzzle answer was `1132`.
+
+Both parts of this puzzle are complete! They provide two gold stars:
+\*\*
+
+At this point, you should [return to your Advent calendar](/2017) and
+try another puzzle.
+
+If you still want to see it, you can [get your puzzle
+input](1/input).

2017/01/solution.py

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+#!/bin/python3
+import sys
+from pprint import pprint
+
+input_f = "input" #sys.argv[1]
+
+arr = []
+
+with open(input_f) as file:
+    for line in file:
+        arr = list(line.rstrip('\n'))
+#########################################
+#                                       #
+#              Part 1                   #
+#                                       #
+#########################################
+sum = 0
+for idx,x in enumerate(arr):
+    if idx != len(arr)-1:
+        if x == arr[idx+1]:
+            sum+=int(x)
+    else:
+        if x == arr[0]:
+            sum+=int(x)
+
+print(sum)
+
+#########################################
+#                                       #
+#              Part 2                   #
+#                                       #
+#########################################
+
+sum=0
+length=len(arr)
+
+for idx,x in enumerate(arr):
+    if idx != length:
+        print(x,arr[(int(length/2)+idx) % length])
+        if x == arr[(int(length/2)+idx) % length]:
+            sum+=int(x)
+
+print(sum)