clean up day 3 slightly

day03/sol.py

@@ -1,13 +1,15 @@
 import string
 letters = string.ascii_lowercase + string.ascii_uppercase
 
-rs = []
+data = []
+
 t = 0
 for line in open("input"):
-    n = len(line.strip())
-    n //= 2
+    data.append(line.strip())
+
+for line in data:
+    n = len(line) // 2
     a, b = line[:n], line[n:]
-    rs.append(set(line[:2*n]))
     u = set(a) & set(b)
     assert len(u) == 1
     x = list(u)[0]
@@ -17,10 +19,10 @@ for line in open("input"):
 print(t)
 
 t = 0
-for i in range(0, len(rs), 3):
-    a, b, c = rs[i:i+3]
-    #print(a & b & c)
+for i in range(0, len(data), 3):
+    a, b, c = map(set, data[i:i+3])
     u = a & b & c
+    #print(u)
     assert len(u) == 1
     x = list(u)[0]
     t += 1 + letters.index(x)