diff --git a/py/2018/03/solve.py b/py/2018/03/solve.py
deleted file mode 100644
index daf5d0e..0000000
--- a/py/2018/03/solve.py
+++ /dev/null
@@ -1,56 +0,0 @@
-import re
-import sys
-
-CLAIM_RE = r"#(\d+) @ (\d+),(\d+): (\d+)x(\d+)\n"
-
-def load_claims(filename):
-	claims = {}
-	with open(filename, "r") as f:
-		for line in f:
-			match = re.fullmatch(CLAIM_RE, line)
-			elf, x, y, w, h = match.groups()
-			elf, x, y, w, h = int(elf), int(x), int(y), int(w), int(h)
-			claims[elf] = (x, y, w, h)
-	return claims
-
-# PART 1
-
-def count_claims(claims):
-	squares = {}
-	for x, y, w, h in claims.values():
-		for dw in range(w):
-			for dh in range(h):
-				coords = (x + dw, y + dh)
-				squares[coords] = squares.get(coords, 0) + 1
-	return squares
-
-def find_doubles(squares):
-	return len(list(filter(lambda x: x > 1, squares.values())))
-
-# PART 2
-
-def is_intact(squares, x, y, w, h):
-	for dw in range(w):
-		for dh in range(h):
-			coords = (x + dw, y + dh)
-			if squares.get(coords, 0) > 1:
-				return False
-	return True
-
-def find_intact_claim(claims, squares):
-	for elf, (x, y, w, h) in claims.items():
-		if is_intact(squares, x, y, w, h):
-			return elf
-
-def main(filename):
-	claims = load_claims(filename)
-	print(f"Solutions for {filename}")
-	squares = count_claims(claims)
-	doubles = find_doubles(squares)
-	print(f"Part 1: {doubles}")
-	intact = find_intact_claim(claims, squares)
-	print(f"Part 2: {intact}")
-
-if __name__ == "__main__":
-	for filename in sys.argv[1:]:
-		main(filename)
diff --git a/py/aoc/__init__.py b/py/aoc/__init__.py
index ce1293e..d03f79a 100644
--- a/py/aoc/__init__.py
+++ b/py/aoc/__init__.py
@@ -2,7 +2,7 @@ import sys
 import argparse
 from pathlib import Path
 
-from .y2018 import d01, d02
+from .y2018 import d01, d02, d03
 from .y2020 import d10
 from .y2021 import d14
 from .y2022 import d01, d02, d03, d04, d05, d06
@@ -10,6 +10,7 @@ from .y2022 import d01, d02, d03, d04, d05, d06
 DAYS = {
     "2018_01": y2018.d01.solve,
     "2018_02": y2018.d02.solve,
+    "2018_03": y2018.d03.solve,
     "2020_10": y2020.d10.solve,
     "2021_14": y2021.d14.solve,
     "2022_01": y2022.d01.solve,
diff --git a/py/aoc/y2018/d03.py b/py/aoc/y2018/d03.py
new file mode 100644
index 0000000..fcdef3d
--- /dev/null
+++ b/py/aoc/y2018/d03.py
@@ -0,0 +1,57 @@
+import re
+
+CLAIM_RE = r"#(\d+) @ (\d+),(\d+): (\d+)x(\d+)"
+
+
+def load_claims(inputstr):
+    claims = {}
+    for line in inputstr.splitlines():
+        match = re.fullmatch(CLAIM_RE, line)
+        elf, x, y, w, h = match.groups()
+        elf, x, y, w, h = int(elf), int(x), int(y), int(w), int(h)
+        claims[elf] = (x, y, w, h)
+    return claims
+
+
+# PART 1
+
+
+def count_claims(claims):
+    squares = {}
+    for x, y, w, h in claims.values():
+        for dw in range(w):
+            for dh in range(h):
+                coords = (x + dw, y + dh)
+                squares[coords] = squares.get(coords, 0) + 1
+    return squares
+
+
+def find_doubles(squares):
+    return len(list(filter(lambda x: x > 1, squares.values())))
+
+
+# PART 2
+
+
+def is_intact(squares, x, y, w, h):
+    for dw in range(w):
+        for dh in range(h):
+            coords = (x + dw, y + dh)
+            if squares.get(coords, 0) > 1:
+                return False
+    return True
+
+
+def find_intact_claim(claims, squares):
+    for elf, (x, y, w, h) in claims.items():
+        if is_intact(squares, x, y, w, h):
+            return elf
+
+
+def solve(inputstr):
+    claims = load_claims(inputstr)
+    squares = count_claims(claims)
+    doubles = find_doubles(squares)
+    print(f"Part 1: {doubles}")
+    intact = find_intact_claim(claims, squares)
+    print(f"Part 2: {intact}")