Add solution to day 5

README.md

@@ -10,3 +10,4 @@ Below are a list of the programming languages used to solve each day:
 - Day 2 - Haskell
 - Day 3 - Rust
 - Day 4 - Rust
+- Day 5 - Python

day5/README.md

@@ -0,0 +1,18 @@
+# Day 4
+
+## Instructions
+
+From the root directory of the crate (where this README is) just execute:
+
+```
+python day5.py
+```
+
+The solution will be printed to the terminal output.
+
+## Notes:
+
+I had very little time so decided to just crank out a quick solution using Python.
+I was under a heavy time constraint so I ended up just implementing the brute force approach instead of designing a better algorithm.
+Hopefully I can do some more algorithmic design for future problems to get better time complexity, even though it doesn't really matter.
+

day5/day5.py

@@ -0,0 +1,77 @@
+# %%
+import itertools
+
+
+# %% Define functions
+def read_file(path):
+    """Read the example input file and return a tuple of rules and orderings"""
+    rules = list()
+    updates = list()
+    with open(path, "r") as f:
+        for line in f:
+            if "|" in line:
+                rules.append(line)
+            elif not line.isspace():
+                updates.append(line)
+    return rules, updates
+
+
+def prepare_rules(rules):
+    """Prepare the rules for use by the analysis algorithm"""
+    return set(rules)
+
+
+def process_updates(updates, rules):
+    sum = 0
+    for update in updates:
+        # Brute force this because I started late
+        nums = [int(val) for val in update.split(",")]
+        correct = True
+        for (i, num1), (j, num2) in itertools.product(enumerate(nums), enumerate(nums)):
+            if i < j:
+                bad_rule = f"{num2}|{num1}\n"
+                if bad_rule in rules:
+                    correct = False
+                    break
+        if correct:
+            sum += nums[int(len(nums) / 2)]
+    return sum
+
+
+def fix_bad_update(update, rules):
+    sum = 0
+    for update in updates:
+        # Brute force this because I started late and don't have time to design a better algorithm
+        nums = [int(val) for val in update.split(",")]
+        fix_count = 0
+        correct = False
+        while correct == False:
+            correct = True
+            for (i, num1), (j, num2) in itertools.product(
+                enumerate(nums), enumerate(nums)
+            ):
+                if i < j:
+                    bad_rule = f"{num2}|{num1}\n"
+                    if bad_rule in rules:
+                        correct = False
+                        fix_count += 1
+                        nums[i] = num2
+                        nums[j] = num1
+                        break
+
+        if fix_count > 0:
+            sum += nums[int(len(nums) / 2)]
+    return sum
+
+
+# %% Execut
+
+if __name__ == "__main__":
+    rules, updates = read_file("./input.txt")
+    rules = prepare_rules(rules)
+    sum = process_updates(updates, rules)
+    print(f"Part1 answer is {sum}")
+    sum = fix_bad_update(updates, rules)
+    print(f"Part2 answer is {sum}")
+
+# %%