diff --git a/src/trio.rs b/src/trio.rs
index 70d111b..4c31222 100644
--- a/src/trio.rs
+++ b/src/trio.rs
@@ -237,7 +237,9 @@ pub fn assign_parental_groups(
         tot >= settings.assign_cnt
             && node_len <= tot * settings.assign_sparsity
             && ((x as f64) > settings.assign_ratio * (y as f64) - 1e-6
-                || (node_len > solid_len && (x as f64) > settings.solid_ratio * (y as f64) - 1e-6 && node_cov < solid_cov - 1e-6))
+                || (node_len > solid_len
+                    && (x as f64) > settings.solid_ratio * (y as f64) - 1e-6
+                    && node_cov < solid_cov - 1e-6))
     };
 
     let issue_node_f = |x: usize, y: usize, node_len: usize| {