Solution to problem 1 in Python

src/Year_2021/P1.py

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+# --- Day 1: Sonar Sweep ---
+
+# You're minding your own business on a ship at sea when the overboard alarm
+# goes off! You rush to see if you can help. Apparently, one of the Elves
+# tripped and accidentally sent the sleigh keys flying into the ocean!
+
+# Before you know it, you're inside a submarine the Elves keep ready for
+# situations like this. It's covered in Christmas lights (because of course it
+# is), and it even has an experimental antenna that should be able to track the
+# keys if you can boost its signal strength high enough; there's a little meter
+# that indicates the antenna's signal strength by displaying 0-50 stars.
+
+# Your instincts tell you that in order to save Christmas, you'll need to get
+# all fifty stars by December 25th.
+
+# Collect stars by solving puzzles. Two puzzles will be made available on each
+# day in the Advent calendar; the second puzzle is unlocked when you complete
+# the first. Each puzzle grants one star. Good luck!
+
+# As the submarine drops below the surface of the ocean, it automatically
+# performs a sonar sweep of the nearby sea floor. On a small screen, the sonar
+# sweep report (your puzzle input) appears: each line is a measurement of the
+# sea floor depth as the sweep looks further and further away from the
+# submarine.
+
+# For example, suppose you had the following report:
+
+# 199
+# 200
+# 208
+# 210
+# 200
+# 207
+# 240
+# 269
+# 260
+# 263
+
+# This report indicates that, scanning outward from the submarine, the sonar
+# sweep found depths of 199, 200, 208, 210, and so on.
+
+# The first order of business is to figure out how quickly the depth increases,
+# just so you know what you're dealing with - you never know if the keys will
+# get carried into deeper water by an ocean current or a fish or something.
+
+# To do this, count the number of times a depth measurement increases from the
+# previous measurement. (There is no measurement before the first measurement.)
+# In the example above, the changes are as follows:
+
+# 199 (N/A - no previous measurement)
+# 200 (increased)
+# 208 (increased)
+# 210 (increased)
+# 200 (decreased)
+# 207 (increased)
+# 240 (increased)
+# 269 (increased)
+# 260 (decreased)
+# 263 (increased)
+
+# In this example, there are 7 measurements that are larger than the previous
+# measurement.
+
+# How many measurements are larger than the previous measurement?
+
+with open("files/P1.txt", "r") as f:
+    report = [int(number) for number in f.read().strip().split()]
+
+
+def part_1(lst: list[int]) -> int:
+    increments = sum(
+        1 for idx, val in enumerate(lst) if idx > 0 and lst[idx] > lst[idx - 1]
+    )
+    return increments
+
+
+if __name__ == "__main__":
+    print(part_1(report))