Day 4: Part 1

day4/main.py

@@ -0,0 +1,24 @@
+with open("day4/input.txt") as file:
+    paperrolls = [str(line.strip("\n")) for line in file.readlines()]
+
+
+h = len(paperrolls)
+w = len(paperrolls[0]) if h>0 else 0
+
+dirs = [(-1,-1),(-1,0),(-1,1),(0,-1),(0,1),(1,-1),(1,0),(1,1)]
+
+def neighbors_count(r,c):
+    cnt = 0
+    for dr,dc in dirs:
+        rr,cc = r+dr, c+dc
+        if 0 <= rr < h and 0 <= cc < w and paperrolls[rr][cc] == '@':
+            cnt += 1
+    return cnt
+
+accessible = 0
+for r in range(h):
+    for c in range(w):
+        if paperrolls[r][c] == '@' and neighbors_count(r,c) < 4:
+            accessible += 1
+
+print(accessible)