Advent of Code 2015 day 1 part 2: solved

2015/day1/problem.txt

@@ -22,4 +22,15 @@ To what floor do the instructions take Santa?
 
 Your puzzle answer was 232.
 
-The first half of this puzzle is complete! It provides one gold star: *
+--- 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?
+
+Your puzzle answer was 1783.
+
+Both parts of this puzzle are complete! They provide two gold stars: **

2015/day1/solution.py

@@ -0,0 +1,35 @@
+import os
+
+
+def get_floor(x: str) -> int:
+    ob = x.count("(")
+    cb = x.count(")")
+
+    return ob - cb
+
+
+def get_first_char_to_basement(x: str) -> int:
+    current_floor = 0
+    for i, char in enumerate(x):
+        if char == '(':
+            current_floor += 1
+        elif char == ')':
+            current_floor -= 1
+        if current_floor < 0:
+            return i + 1
+
+
+if __name__ == "__main__":
+    assert get_floor("(())") == 0 and get_floor("()()") == 0, "Error: Example 1 doesn't compute"
+    assert get_floor("(((") == 3 and get_floor("(()(()(") == 3, "Error: Example 2 doesn't compute"
+    assert get_floor("))(((((") == 3, "Error: Example 3 doesn't compute"
+    assert get_floor("())") == -1 and get_floor("))(") == -1, "Error: Example 4 doesn't compute"
+    assert get_floor(")))") == -3 and get_floor(")())())") == -3, "Error: Example 4 doesn't compute"
+
+    assert get_first_char_to_basement(")") == 1, "Error: Part2: Example 1 doesn't compute"
+    assert get_first_char_to_basement("()())") == 5, "Error: Part2: Example 2 doesn't compute"
+
+    puzzle_input = open("day1/input.txt", "r").readline()
+    print("Puzzle Input:", puzzle_input)
+    print("solution part1:", get_floor(puzzle_input))
+    print("solution part2:", get_first_char_to_basement(puzzle_input))