Solution to problem 1 in Python

src/Year_2015/P1.py

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+# --- Day 1: Not Quite Lisp ---
+
+# Santa was hoping for a white Christmas, but his weather machine's "snow"
+# function is powered by stars, and he's fresh out! To save Christmas, he needs
+# you to collect fifty stars by December 25th.
+
+# Collect stars by helping Santa solve 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!
+
+# Here's an easy puzzle to warm you up.
+
+# Santa is trying to deliver presents in a large apartment building, but he
+# can't find the right floor - the directions he got are a little confusing.
+# He starts on the ground floor (floor 0) and then follows the instructions
+# one character at a time.
+
+# An opening parenthesis, (, means he should go up one floor, and a closing
+# parenthesis, ), means he should go down one floor.
+
+# The apartment building is very tall, and the basement is very deep; he will
+# never find the top or bottom floors.
+
+# For example:
+
+#     (()) and ()() both result in floor 0.
+#     ((( and (()(()( both result in floor 3.
+#     ))((((( also results in floor 3.
+#     ()) and ))( both result in floor -1 (the first basement level).
+#     ))) and )())()) both result in floor -3.
+
+# To what floor do the instructions take Santa?
+
+with open("files/P1.txt") as f:
+    directions = [line for line in f.read().strip().split()]
+
+
+def part_1() -> None:
+    up = int(directions[0].count("("))
+    down = int(directions[0].count(")"))
+    print(f"The floor is {up - down}")
+
+
+# --- Part Two ---
+
+# Now, given the same instructions, find the position of the first character
+# that causes him to enter the basement (floor -1). The first character in the
+# instructions has position 1, the second character has position 2, and so on.
+
+# For example:
+
+#     ) causes him to enter the basement at character position 1.
+#     ()()) causes him to enter the basement at character position 5.
+
+# What is the position of the character that causes Santa to first enter the
+# basement?
+
+
+def part_2() -> None:
+    floor = 0
+    for idx, char in enumerate(directions[0], start=1):
+        if char == "(":
+            floor += 1
+        elif char == ")":
+            floor -= 1
+        if floor == -1:
+            print(f"The position is {idx}")
+            break
+
+
+if __name__ == "__main__":
+    part_1()
+    part_2()