diff --git a/src/main.rs b/src/main.rs
index 4eab1c2..5efd5c2 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,22 +1,15 @@
-use eframe::{App, CreationContext, NativeOptions, run_native};
+use eframe::{App, NativeOptions, run_native};
 use egui::{Context, Key};
 use egui_graphs::{DefaultGraphView, Graph, SettingsInteraction};
-use petgraph::prelude::{EdgeIndex, NodeIndex, StableGraph};
+use petgraph::prelude::{EdgeIndex, NodeIndex};
 
-pub struct BrainWave {
-    g: Graph,
-}
-
-impl BrainWave {
-    fn new(_: &CreationContext<'_>) -> Self {
-        let g = generate_graph();
-        Self { g: Graph::from(&g) }
-    }
-}
+mod r#static;
+pub use r#static::BrainWave;
 
 impl App for BrainWave {
     fn update(&mut self, ctx: &Context, _: &mut eframe::Frame) {
         egui::CentralPanel::default().show(ctx, |ui| {
+            // graph viewer
             ui.add(
                 &mut DefaultGraphView::new(&mut self.g).with_interactions(
                     &SettingsInteraction::new()
@@ -27,7 +20,9 @@ impl App for BrainWave {
                         .with_edge_selection_multi_enabled(true),
                 ),
             );
+            // input event handler
             ui.input(|input| {
+                // delete
                 if input.key_pressed(Key::Delete) {
                     handle_graph_delete(&mut self.g);
                 }
@@ -36,54 +31,39 @@ impl App for BrainWave {
     }
 }
 
-fn generate_graph() -> StableGraph<(), ()> {
-    let mut g = StableGraph::new();
-
-    let a = g.add_node(());
-    let b = g.add_node(());
-    let c = g.add_node(());
-
-    g.add_edge(a, b, ());
-    g.add_edge(b, c, ());
-
-    g
-}
-
 fn handle_graph_delete(graph: &mut Graph) {
-    enum EdgeOrNode {
+    enum EdgeOrNodeIndex {
         Edge(EdgeIndex),
         Node(NodeIndex),
     }
-    let mut to_remove = Vec::new();
-    {
-        let snodes = graph.selected_nodes();
-        let sedges = graph.selected_edges();
-        if snodes.len() + sedges.len() != 0 {
-            for node in snodes {
-                to_remove.push(EdgeOrNode::Node(*node));
+    graph
+        .selected_nodes()
+        .iter()
+        .copied()
+        .map(EdgeOrNodeIndex::Node)
+        .chain(
+            graph
+                .selected_edges()
+                .iter()
+                .copied()
+                .map(EdgeOrNodeIndex::Edge),
+        )
+        .collect::<Vec<EdgeOrNodeIndex>>()
+        .into_iter()
+        .for_each(|e| match e {
+            EdgeOrNodeIndex::Node(node) => {
+                graph.remove_node(node);
             }
-            for edge in sedges {
-                to_remove.push(EdgeOrNode::Edge(*edge));
+            EdgeOrNodeIndex::Edge(edge) => {
+                graph.remove_edge(edge);
             }
-        }
-    }
-    for e in to_remove {
-        match e {
-            EdgeOrNode::Edge(edge_index) => {
-                graph.remove_edge(edge_index);
-            }
-            EdgeOrNode::Node(node_index) => {
-                graph.remove_node(node_index);
-            }
-        }
-    }
+        })
 }
 
-fn main() {
+fn main() -> eframe::Result {
     run_native(
         "basic",
         NativeOptions::default(),
         Box::new(|cc| Ok(Box::new(BrainWave::new(cc)))),
     )
-    .unwrap();
 }