diff --git a/src/day09.zig b/src/day09.zig
index f4ae708..25438f1 100644
--- a/src/day09.zig
+++ b/src/day09.zig
@@ -46,14 +46,10 @@ fn solve(alloc: mem.Allocator, input: []const u8) !Solution {
         // Extrapolate
         var next: isize = 0;
         var prev: isize = 0;
-        for (seqs.items) |seq| {
-            next += seq[seq.len - 1];
-        }
         for (0..seqs.items.len) |i| {
-            prev = seqs.items[seqs.items.len - i - 1][0] - prev;
-        }
-        for (seqs.items) |seq| {
-            // Clean up
+            const seq = seqs.items[seqs.items.len - i - 1];
+            prev = seq[0] - prev;
+            next += seq[seq.len - 1];
             alloc.free(seq);
         }
         prev_sum += prev;