diff --git a/src/board.rs b/src/board.rs
index 345de42..e87e44c 100644
--- a/src/board.rs
+++ b/src/board.rs
@@ -52,25 +52,22 @@ fn gen_adj_lookup() -> PosMap<ChainCollection> {
                     split_from(0..=BOARD_SIZE - 1, j),
                 );
 
-                let mut chains: ChainCollection = ArrayVec::new_const();
-
-                chains.extend(
+                let chains: ChainCollection = ArrayVec::from_iter(
                     i_chain
                         .clone()
+                        .into_iter()
                         .map(|range| range.map(move |i| (i, j)))
-                        .map(Iterator::collect),
+                        .map(Iterator::collect)
+                        .chain(
+                            j_chain
+                                .clone()
+                                .into_iter()
+                                .map(|range| range.map(move |j| (i, j)))
+                                .map(Iterator::collect),
+                        )
+                        .chain(diag_raw(i_chain, j_chain).map(Iterator::collect)),
                 );
 
-                chains.extend(
-                    j_chain
-                        .clone()
-                        .map(|range| range.map(move |j| (i, j)))
-                        .map(Iterator::collect),
-                );
-
-                // handle diagonals
-                chains.extend(diag_raw(i_chain, j_chain).map(Iterator::collect));
-
                 // make sure all chains are in the proper range so we can ignore bounds checking later
                 assert!(
                     chains