AoC 2021: day 5 solutions

Signed-off-by: Ettore Dreucci <ettore.dreucci@gmail.com>

2021/solutions/day_05.py

@@ -0,0 +1,89 @@
+"""AOC Day 5"""
+
+import pathlib
+import time
+import collections
+
+TEST_INPUT = """0,9 -> 5,9
+8,0 -> 0,8
+9,4 -> 3,4
+2,2 -> 2,1
+7,0 -> 7,4
+6,4 -> 2,0
+0,9 -> 2,9
+3,4 -> 1,4
+0,0 -> 8,8
+5,5 -> 8,2"""
+
+def read_input(input_path: str) -> str:
+    """take input file path and return a str with the file's content"""
+    with open(input_path, 'r') as input_file:
+        input_data = input_file.read().strip()
+        return input_data
+
+def extract(input_data: str) -> list:
+    """take input data and return the appropriate data structure"""
+    lines = list()
+    for line in input_data.splitlines():
+        a, b = line.split('->')
+        ax, ay = map(int, a.split(','))
+        bx, by = map(int, b.split(','))
+        lines.append((ax, ay, bx, by))
+    return lines
+
+def part1(entries: list, space: collections.defaultdict) -> int:
+    """part1 solver take the entries and return the part1 solution"""
+    for ax, ay, bx, by in entries:
+        if ax == bx:
+            for y in range(min(ay, by), max(ay, by) + 1):
+                space[ax, y] += 1
+        elif ay == by:
+            for x in range(min(ax, bx), max(ax, bx) + 1):
+                space[x, ay] += 1
+    
+    return sum(v > 1 for v in space.values())
+
+
+def part2(entries: list, space: collections.defaultdict) -> int:
+    """part2 solver take the entries and return the part2 solution"""
+    for ax, ay, bx, by in entries:
+        if ax != bx and ay != by:
+            for i in range(abs(ax-bx)+1):
+                if ax < bx:
+                    if ay < by:
+                        space[ax+i, ay+i] += 1
+                    else:
+                        space[ax+i, ay-i] += 1
+                else:
+                    if ay < by:
+                        space[ax-i, ay+i] += 1
+                    else:
+                        space[ax-i, ay-i] += 1
+        
+    return sum(v > 1 for v in space.values())
+
+def test_input_day_05():
+    """pytest testing function"""
+    entries = extract(TEST_INPUT)
+    space = collections.defaultdict(int)
+    assert part1(entries, space) == 5
+    assert part2(entries, space) == 12
+
+def test_bench_day_05(benchmark):
+    """pytest-benchmark function"""
+    benchmark(main)
+
+def main():
+    """main function"""
+    input_path = str(pathlib.Path(__file__).resolve().parent.parent) + "/inputs/" + str(pathlib.Path(__file__).stem)
+    start_time = time.time()
+    input_data = read_input(input_path)
+    entries = extract(input_data)
+    space = collections.defaultdict(int)
+    print("Part 1: %d" % part1(entries, space))
+    print("Part 2: %d" % part2(entries, space))
+    end_time = time.time()
+    print("Execution time: %f" % (end_time-start_time))
+
+if __name__ == "__main__":
+    main()