diff --git a/14/14.py b/14/14.py
index 9825834..9f03472 100755
--- a/14/14.py
+++ b/14/14.py
@@ -35,10 +35,10 @@ poly, rules = parse_file('input.txt')
 print(f'poly: {poly}')
 print(f'rules: {rules}')
 
-for s in range(10):
+for s in range(13):
     print(f'step: {s}')
     poly = step_poly(poly, rules)
-    print(poly)
+    #print(poly)
 
 print(Counter(poly))
 c = Counter(poly).most_common()[0][1] - Counter(poly).most_common()[-1][1]
diff --git a/14/14_2.py b/14/14_2.py
new file mode 100755
index 0000000..9eb17ca
--- /dev/null
+++ b/14/14_2.py
@@ -0,0 +1,71 @@
+#!/usr/bin/env python
+# 2021 - Advent Of Code - 14 part 2
+
+from collections import Counter
+
+
+def parse_file(file):
+    poly_list = []
+    insertion_rules = {}
+    with open(file) as f:
+        poly_str = list(f.readline().strip())
+
+        for i, p in enumerate(poly_str):
+            if i + 1 == len(poly_str):
+                break
+            pair = '' + p + poly_str[i + 1]
+            poly_list.append(pair)
+        f.readline()
+
+        for line in f.readlines():
+            pair, insert = line.strip().split(' -> ')
+            insertion_rules[pair] = [pair[0] + insert, insert + pair[1]]
+
+        f_l = poly_str[0], poly_str[-1]
+
+        return poly_list, insertion_rules, f_l
+
+
+def step_poly(init_count, ruleset):
+    new_count = dict.fromkeys(ruleset.keys(), 0)
+    for p in init_count.keys():
+        nb = init_count[p]
+        p1, p2 = ruleset[p]
+        new_count[p1] += nb
+        new_count[p2] += nb
+
+    return new_count
+
+
+# poly, rules, first_last = parse_file('input_example.txt')
+poly, rules, first_last = parse_file('input.txt')
+print(f'poly: {poly}')
+print(f'rules: {rules}')
+
+poly_count = dict.fromkeys(rules.keys(), 0)
+for polymer in poly:
+    poly_count[polymer] += 1
+print(f'init count: {poly_count}')
+
+for s in range(40):
+    # print(f'step: {s}')
+    poly_count = step_poly(poly_count, rules)
+
+print(f'poly count: {poly_count}')
+
+elements = set([k for key in poly_count.keys() for k in (key[0], key[1])])
+print(f'elements: {elements}')
+elem_count = dict.fromkeys(elements, 0)
+
+for polymer in poly_count.keys():
+    elem_count[polymer[0]] += poly_count[polymer]
+    elem_count[polymer[1]] += poly_count[polymer]
+
+# remove double count, and fix first and last element
+elem_count[first_last[0]] += 1
+elem_count[first_last[1]] += 1
+elem_count = {k: int(v/2) for k, v in elem_count.items()}
+print(f'fixed elem count: {elem_count}')
+
+c = Counter(elem_count).most_common()[0][1] - Counter(elem_count).most_common()[-1][1]
+print(c)
diff --git a/14/14_2_bad.py b/14/14_2_bad.py
new file mode 100755
index 0000000..1273dc7
--- /dev/null
+++ b/14/14_2_bad.py
@@ -0,0 +1,49 @@
+#!/usr/bin/env python
+# 2021 - Advent Of Code - 14 part 2
+
+from collections import Counter
+
+
+def parse_file(file):
+    with open(file) as f:
+        poly_string = list(f.readline().strip())
+        f.readline()
+        insertion_rules = dict([line.strip().split(' -> ') for line in f.readlines()])
+
+        return poly_string, insertion_rules
+
+
+def step_poly(poly_str, ruleset):
+    new_p = []
+    l_poly = len(poly_str)
+    for i, p in enumerate(poly_str):
+        if i + 1 == l_poly:
+            break
+        binome = '' + p + poly_str[i+1]
+        # print(f'binome {binome}')
+        found = ruleset.get(binome)
+        #if found:
+        #    # print(f'found: {found}')
+        #    new_p.extend([p, found])
+        #else:
+        #    new_p.append(p)
+        new_p.extend([p, found])
+
+    new_p.append(p)
+    return ''.join(new_p)
+
+
+# poly, rules = parse_file('input_example.txt')
+poly, rules = parse_file('input.txt')
+print(f'poly: {poly}')
+print(f'rules: {rules}')
+
+for s in range(22):
+#for s in range(17):
+    print(f'step: {s}')
+    poly = step_poly(poly, rules)
+    # print(poly)
+
+print(Counter(poly))
+c = Counter(poly).most_common()[0][1] - Counter(poly).most_common()[-1][1]
+print(c)