diff --git a/day22.py b/day22.py
new file mode 100644
index 0000000..2d36fad
--- /dev/null
+++ b/day22.py
@@ -0,0 +1,57 @@
+#!/usr/bin/env python3
+
+from collections import defaultdict
+
+initial_secrets = []
+
+with open("day22") as f:
+    initial_secrets = list(map(int, f))
+
+def calc_secrets(init: int, cnt: int) -> list[int]:
+    sec = init
+    col = [init]
+    for _ in range(cnt):
+        sec = (sec ^ (sec * 64)) % 16777216
+        sec = (sec ^ (sec // 32)) % 16777216
+        sec = (sec ^ (sec * 2048)) % 16777216
+        col.append(sec)
+    return col
+
+# part 1
+res = 0
+for init in initial_secrets:
+    secrets = calc_secrets(init, 2000)
+    res += secrets[-1]
+
+print(res)
+
+# part 2
+def calc_prices(init: int, cnt: int) -> list[int]:
+    return [s%10 for s in calc_secrets(init, cnt)]
+
+def calc_diffs(prices: list[int]) -> list[int]:
+    return [0] + [b-a for a,b in zip(prices, prices[1:])]
+
+def calc_seq_price(prices, diffs):
+    seq_price = {}
+    for i in range(0,len(diffs)-4):
+        seq = (diffs[i], diffs[i+1], diffs[i+2], diffs[i+3])
+        price = prices[i+3]
+
+        if seq not in seq_price:
+            seq_price[seq] = price
+
+    return seq_price
+
+
+all_prices = [calc_prices(init, 2000) for init in initial_secrets]
+all_diffs = [calc_diffs(prices) for prices in all_prices]
+all_seq_prices = [calc_seq_price(prices, diffs) for prices,diffs in zip(all_prices, all_diffs)]
+
+seq_price_total = defaultdict(int)
+for seq_price in all_seq_prices:
+    for s,p in seq_price.items():
+        seq_price_total[s] += p
+
+max_seq, max_price = sorted(seq_price_total.items(), key=lambda x: x[1], reverse=True)[0]
+print(max_price)