Solution to problem 2

src/Year_2017/P2.py

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+# --- Day 2: Corruption Checksum ---
+
+# As you walk through the door, a glowing humanoid shape yells in your
+# direction. "You there! Your state appears to be idle. Come help us repair the
+# corruption in this spreadsheet - if we take another millisecond, we'll have
+# to display an hourglass cursor!"
+
+# The spreadsheet consists of rows of apparently-random numbers. To make sure
+# the recovery process is on the right track, they need you to calculate the
+# spreadsheet's checksum. For each row, determine the difference between the
+# largest value and the smallest value; the checksum is the sum of all of these
+# differences.
+
+# For example, given the following spreadsheet:
+
+# 5 1 9 5
+# 7 5 3
+# 2 4 6 8
+
+#     The first row's largest and smallest values are 9 and 1, and their
+# difference is 8.
+#     The second row's largest and smallest values are 7 and 3, and their
+# difference is 4.
+#     The third row's difference is 6.
+
+# In this example, the spreadsheet's checksum would be 8 + 4 + 6 = 18.
+
+# What is the checksum for the spreadsheet in your puzzle input?
+
+from itertools import combinations
+
+with open("files/P2.txt") as f:
+    str_spreadsheet: list[list[str]] = [
+        line.split("\t") for line in f.read().strip().split("\n")
+    ]
+    int_spreadsheet: list[list[int]] = [
+        [int(num) for num in row] for row in str_spreadsheet
+    ]
+
+
+def part_1() -> None:
+    print(
+        f"Checksum is {sum(max(line) - min(line) for line in int_spreadsheet)}"
+    )
+
+
+# --- Part Two ---
+
+# "Great work; looks like we're on the right track after all. Here's a star for
+# your effort." However, the program seems a little worried. Can programs be
+# worried?
+
+# "Based on what we're seeing, it looks like all the User wanted is some
+# information about the evenly divisible values in the spreadsheet.
+# Unfortunately, none of us are equipped for that kind of calculation - most of
+# us specialize in bitwise operations."
+
+# It sounds like the goal is to find the only two numbers in each row where one
+# evenly divides the other - that is, where the result of the division
+# operation is a whole number. They would like you to find those numbers on
+# each line, divide them, and add up each line's result.
+
+# For example, given the following spreadsheet:
+
+# 5 9 2 8
+# 9 4 7 3
+# 3 8 6 5
+
+#     In the first row, the only two numbers that evenly divide are 8 and 2;
+# the result of this division is 4.
+#     In the second row, the two numbers are 9 and 3; the result is 3.
+#     In the third row, the result is 2.
+
+# In this example, the sum of the results would be 4 + 3 + 2 = 9.
+
+# What is the sum of each row's result in your puzzle input?
+
+
+def part_2() -> None:
+    result = []
+    for row in int_spreadsheet:
+        pairs = combinations(row, 2)
+        for el1, el2 in pairs:
+            if el1 % el2 == 0:
+                result.append(int(el1 / el2))
+                break
+            elif el2 % el1 == 0:
+                result.append(int(el2 / el1))
+                break
+
+    print(f"Sum of each row's result is {sum(result)}")
+
+
+if __name__ == "__main__":
+    part_1()
+    part_2()