Solved 2024/02 P1 + P2

2024/02/2.md

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+## \-\-- Day 2: Red-Nosed Reports \-\--
+
+Fortunately, the first location The Historians want to search isn\'t a
+long walk from the Chief Historian\'s office.
+
+While the [Red-Nosed Reindeer nuclear fusion/fission
+plant](/2015/day/19) appears to contain no sign of the Chief Historian,
+the engineers there run up to you as soon as they see you. Apparently,
+they *still* talk about the time Rudolph was saved through molecular
+synthesis from a single electron.
+
+They\'re quick to add that - since you\'re already here - they\'d really
+appreciate your help analyzing some unusual data from the Red-Nosed
+reactor. You turn to check if The Historians are waiting for you, but
+they seem to have already divided into groups that are currently
+searching every corner of the facility. You offer to help with the
+unusual data.
+
+The unusual data (your puzzle input) consists of many *reports*, one
+report per line. Each report is a list of numbers called *levels* that
+are separated by spaces. For example:
+
+    7 6 4 2 1
+    1 2 7 8 9
+    9 7 6 2 1
+    1 3 2 4 5
+    8 6 4 4 1
+    1 3 6 7 9
+
+This example data contains six reports each containing five levels.
+
+The engineers are trying to figure out which reports are *safe*. The
+Red-Nosed reactor safety systems can only tolerate levels that are
+either gradually increasing or gradually decreasing. So, a report only
+counts as safe if both of the following are true:
+
+-   The levels are either *all increasing* or *all decreasing*.
+-   Any two adjacent levels differ by *at least one* and *at most
+    three*.
+
+In the example above, the reports can be found safe or unsafe by
+checking those rules:
+
+-   `7 6 4 2 1`: *Safe* because the levels are all decreasing by 1 or 2.
+-   `1 2 7 8 9`: *Unsafe* because `2 7` is an increase of 5.
+-   `9 7 6 2 1`: *Unsafe* because `6 2` is a decrease of 4.
+-   `1 3 2 4 5`: *Unsafe* because `1 3` is increasing but `3 2` is
+    decreasing.
+-   `8 6 4 4 1`: *Unsafe* because `4 4` is neither an increase or a
+    decrease.
+-   `1 3 6 7 9`: *Safe* because the levels are all increasing by 1, 2,
+    or 3.
+
+So, in this example, `2` reports are *safe*.
+
+Analyze the unusual data from the engineers. *How many reports are
+safe?*
+
+Your puzzle answer was `252`.
+
+## \-\-- Part Two \-\-- {#part2}
+
+The engineers are surprised by the low number of safe reports until they
+realize they forgot to tell you about the [Problem
+Dampener]{title="I need to get one of these!"}.
+
+The Problem Dampener is a reactor-mounted module that lets the reactor
+safety systems *tolerate a single bad level* in what would otherwise be
+a safe report. It\'s like the bad level never happened!
+
+Now, the same rules apply as before, except if removing a single level
+from an unsafe report would make it safe, the report instead counts as
+safe.
+
+More of the above example\'s reports are now safe:
+
+-   `7 6 4 2 1`: *Safe* without removing any level.
+-   `1 2 7 8 9`: *Unsafe* regardless of which level is removed.
+-   `9 7 6 2 1`: *Unsafe* regardless of which level is removed.
+-   `1 3 2 4 5`: *Safe* by removing the second level, `3`.
+-   `8 6 4 4 1`: *Safe* by removing the third level, `4`.
+-   `1 3 6 7 9`: *Safe* without removing any level.
+
+Thanks to the Problem Dampener, `4` reports are actually *safe*!
+
+Update your analysis by handling situations where the Problem Dampener
+can remove a single level from unsafe reports. *How many reports are now
+safe?*
+
+Your puzzle answer was `324`.
+
+Both parts of this puzzle are complete! They provide two gold stars:
+\*\*
+
+At this point, you should [return to your Advent calendar](/2024) and
+try another puzzle.
+
+If you still want to see it, you can [get your puzzle
+input](2/input).
+

2024/02/solution.py

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+#!/bin/python3
+import sys,re
+from pprint import pprint
+sys.path.insert(0, '../../')
+from fred import list2int,get_re,nprint,lprint
+
+input_f = 'input'
+
+part = 2
+#########################################
+#                                       #
+#              Part 1                   #
+#                                       #
+#########################################
+
+def checkInc(line:list):
+    safe = False
+    for i in range(0,len(line)-1):
+        if line[i] < line[i+1]:
+            safe = True  
+        else:
+            return False
+    return safe
+
+def checkDesc(line:list):
+    safe = False
+    for i in range(0,len(line)-1):  
+        if line[i] > line[i+1]:
+            safe = True
+        else:
+            return False
+    return safe
+
+def checkJump(line:list):
+    safe = False
+    for i in range(0,len(line)-1):
+        if abs(line[i] - line[i+1]) in [1,2,3]:
+            safe = True  
+        else:
+            return False
+    return safe
+
+
+if part == 1:
+    reports = []
+    count = 0
+    with open(input_f) as file:
+        for line in file:
+            reports.append(list2int(line.rstrip().split()))
+
+    for r in reports:
+        if (checkDesc(r) or checkInc(r)) and checkJump(r):
+            count += 1
+    print(count)
+
+
+
+#########################################
+#                                       #
+#              Part 2                   #
+#                                       #
+#########################################
+if part == 2:
+    reports = []
+    count = 0
+    j = 0
+    with open(input_f) as file:
+        for line in file:
+            reports.append(list2int(line.rstrip().split()))
+
+    for rdx,r in enumerate(reports):
+        if (checkDesc(r) or checkInc(r)) and checkJump(r):
+            count += 1
+        else:
+            secondSafe = False
+            while not secondSafe:
+                tmp = r[:j] + r[j + 1:]
+                if (checkDesc(tmp) or checkInc(tmp)) and checkJump(tmp):
+                    count += 1
+                    secondSafe = True
+                
+                if not secondSafe and j > len(tmp)-1:
+                    break
+                j += 1
+            j = 0
+            secondSafe = False
+                
+    print(count)

2024/02/test2

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+8 6 4 4 1

2024/02/test3

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+1 1 2
+2 6 1

README.md

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 ## 2024
 
            .--'~ ~ ~|        .-' *       \  /     '-.   1 **
-
+        .--'~  ,* ~ |        |  <o>   \_\_\|_/__/   |   2 **
 ## 2023
 
                       .      * ~~~~  /\ ' .            14 
@@ -62,7 +62,7 @@
 
     .-----------------------------------------------.       
     | o──────*──────┐o┬──────────────────┐┌───────┐ |  25 *
-    | o──*──┐└───┐o─┴─┘o────────┬─────o┌─┘├───o┌──┤ |  24 *
+    | o──*──┐└───┐o─┴─┘o────────┬─────o┌─┘├───o┌──┤ |  24 **
     | ┌──┘o─┴────┘┌────────────*├──────┘o─┘┌───┘┌─┘ |  23 *
     | ├───┐┌──────┴o*──|(────┐┌┘└──────────┘o┬──┘o┐ |  22 **
     | └┐o┐└┘*───────┘o┬─┬──┬┴┴┴┬───┬┴┴┴┴┬───┐└────┤ |  21 **