Update app.py

app.py

@@ -356,6 +356,22 @@ def longest_cib(d: int):
         seq.append(g)
     return seq
 
+def longest_sym_cib(d: int):
+    """
+    Return a predefined longest symmetric coil-in-the-box
+    for certain dimensions, otherwise fall back to a trivial path.
+    """
+    presets = {
+        4: [0, 1, 3, 7, 15, 14, 12, 8, 0],
+        5: [0, 1, 3, 7, 15, 31, 29, 21, 20, 22, 18, 26, 10, 8, 0],
+        6: [0, 1, 3, 7, 15, 13, 29, 28, 20, 22, 18, 50, 48, 56, 57, 59, 63, 55, 53, 37, 36, 44, 46, 42, 10, 8, 0],
+    }
+
+    if d in presets:
+        return presets[d][:]  # return a copy
+
+    return [0]
+
 
 def shorter_cib(d: int):
     """
@@ -748,6 +764,8 @@ app.layout = html.Div(
                 html.Button("Set path", id="btn_set", n_clicks=0),
                 html.Button("Longest CIB", id="btn_longest_cib", n_clicks=0,
                             style={"background": "#059669", "color": "white"}),
+                html.Button("Longest Symmetric CIB", id="btn_longest_sym_cib", n_clicks=0,
+                            style={"background": "#7DD3FC", "color": "#0B1220"}),
                 html.Button("Shorter CIB", id="btn_shorter_cib", n_clicks=0,
                             style={"background": "#00C04B", "color": "white"}),
                 html.Button("Clear", id="btn_clear", n_clicks=0),
@@ -850,6 +868,7 @@ def stats(d, path):
     Input("fig", "clickData"),
     Input("btn_clear", "n_clicks"),
     Input("btn_longest_cib", "n_clicks"),
+    Input("btn_longest_sym_cib", "n_clicks"),
     Input("btn_shorter_cib", "n_clicks"),
     Input("btn_set", "n_clicks"),
     Input("btn_swap", "n_clicks"),
@@ -868,6 +887,7 @@ def stats(d, path):
 def update_path(clickData,
                 n_clear,
                 n_longest,
+                n_longest_sym,
                 n_shorter,
                 n_set,
                 n_swap,
@@ -897,7 +917,12 @@ def update_path(clickData,
     if trigger == "btn_longest_cib":
         return longest_cib(d), {"active": False, "start_idx": None, "end_idx": None}
 
-    # 2b) Shorter CIB
+    # 2b) Longest Symmetric CIB
+    if trigger == "btn_longest_sym_cib":
+        return longest_sym_cib(d), {"active": False, "start_idx": None, "end_idx": None}
+
+    
+    # 2c) Shorter CIB
     if trigger == "btn_shorter_cib":
         return shorter_cib(d), {"active": False, "start_idx": None, "end_idx": None}