1 files changed, 13 insertions, 0 deletions
diff --git a/2023/09/solve.py b/2023/09/solve.py
new file mode 100644
index 0000000..aa9ec70
--- /dev/null
+++ b/2023/09/solve.py
@@ -0,0 +1,13 @@
+L = [[int(n) for n in l.strip().split(" ")] for l in open("input").readlines()]
+
+
+def predict(s):
+    f = []
+    while s:
+        f.append(s[-1])
+        s = [s[i] - s[i - 1] for i in range(1, len(s))]
+    return sum(f)
+
+
+print(sum(predict(l) for l in L))
+print(sum(predict(l[::-1]) for l in L))