8, 10

2 files changed, 106 insertions, 0 deletions

diff --git a/10.py b/10.py
new file mode 100644
index 0000000..27dbde9
--- /dev/null
+++ b/10.py
@@ -0,0 +1,42 @@
+from dataclasses import dataclass
+
+@dataclass
+class Cycle:
+    pass
+
+@dataclass
+class Change:
+    diff: int
+
+instrs = []
+with open('10.in') as f:
+    for line in f:
+        match line.rstrip().split():
+            case ['addx', n]:
+                instrs.append(Cycle())
+                instrs.append(Cycle())
+                instrs.append(Change(int(n)))
+            case ['noop']:
+                instrs.append(Cycle())
+
+cycle = 0
+sigstr = 0
+X = 1
+screen = [0 for _ in range(240)]
+for instr in instrs:
+    match instr:
+        case Cycle():
+            cycle += 1
+            if (cycle - 20) % 40 == 0:
+                sigstr += cycle * X
+            xpos = (cycle - 1) % 40
+            if xpos - 1 <= X <= xpos + 1:
+                screen[cycle - 1] = 1
+        case Change(diff):
+            X += diff
+print(sigstr)
+for y in range(6):
+    line = []
+    for x in range(40):
+        line.append('#' if screen[x + 40 * y] else ' ')
+    print(''.join(line))
diff --git a/8.py b/8.py
new file mode 100644
index 0000000..152517c
--- /dev/null
+++ b/8.py
@@ -0,0 +1,64 @@
+from functools import reduce
+
+with open('8.in') as f:
+    grid = [[int(c) for c in line.rstrip()] for line in f]
+
+visible = set()
+
+for y, row in enumerate(grid):
+    height = -1
+    for x, t in enumerate(row):
+        if t > height:
+            visible.add((x, y))
+            height = t
+    height = -1
+    for x, t in reversed(list(enumerate(row))):
+        if t > height:
+            visible.add((x, y))
+            height = t
+
+for x in range(len(grid[0])):
+    height = -1
+    for y, row in enumerate(grid):
+        t = row[x]
+        if t > height:
+            visible.add((x, y))
+            height = t
+    height = -1
+    for y, row in reversed(list(enumerate(grid))):
+        t = row[x]
+        if t > height:
+            visible.add((x, y))
+            height = t
+
+print(len(visible))
+
+def calc_scenic(grid, x, y):
+    height = grid[y][x]
+    scores = [0 for _ in range(4)]
+    for nx in range(x+1, len(grid[y])):
+        # print('right', nx, y)
+        scores[0] += 1
+        if grid[y][nx] >= height:
+            break
+    for nx in range(x-1, -1, -1):
+        # print('left', nx, y)
+        scores[1] += 1
+        if grid[y][nx] >= height:
+            break
+    for ny in range(y+1, len(grid)):
+        # print('down', x, ny)
+        scores[2] += 1
+        if grid[ny][x] >= height:
+            break
+    for ny in range(y-1, -1, -1):
+        # print('up', x, ny)
+        scores[3] += 1
+        if grid[ny][x] >= height:
+            break
+    # print(scores)
+    return reduce(lambda x, y: x * y, scores, 1)
+
+maxscore = 0
+# print(calc_scenic(grid, 2, 3))
+print(max(calc_scenic(grid, x, y) for x in range(len(grid[0])) for y in range(len(grid))))