another coding evening

05/solve02.py

@@ -0,0 +1,45 @@
+#!/usr/bin/env python
+
+def read_input():
+    with open('input.txt', 'r') as f:
+        data = f.read().splitlines()
+        return data[0]
+
+def find_longest_match(polymer):
+    result = 1
+    for x in range(len(polymer)-1):
+        if abs(ord(polymer[x]) - ord(polymer[x+1])) != 32:
+            break
+        result += 1
+    return result
+            
+
+def retract_polymer(polymer):
+    parsing_pos = 0
+
+    while parsing_pos < len(polymer):
+        lm = find_longest_match(polymer[parsing_pos:])
+        if lm < 2:
+            parsing_pos += 1
+            continue
+
+        lm = 2
+        if parsing_pos == 0:
+            polymer = polymer[lm:]
+        else:
+            polymer = polymer[:parsing_pos] + polymer[lm+parsing_pos:]
+            parsing_pos -= 1
+
+    return len(polymer)
+
+l = []
+for c in range(ord('a'),ord('z')+1):
+    p = read_input()
+    if chr(c) not in p:
+        continue
+    p = p.replace(chr(c), '')
+    p = p.replace(chr(c-32), '')
+    print("removing characher: {}".format(chr(c)))
+    l.append(retract_polymer(p))
+
+print(min(l))