Update app.py

app.py

@@ -23,7 +23,80 @@ sidebar_option = st.sidebar.radio("Select an option",
                                   "Drawing: Simple Path", "Drawing: Spectral Embedding", "Drawing: Traveling Salesman Problem",
                                   "Drawing: Weighted Graph", "3D Drawing: Animations of 3D Rotation", "3D Drawing: Basic Matplotlib",
                                   "Graph: DAG - Topological Layout", "Graph: Erdos Renyi", "Graph: Karate Club", "Graph: Minimum Spanning Tree",
-                                  "Graph: Triads", "Algorithms: Cycle Detection"])
+                                  "Graph: Triads", "Algorithms: Cycle Detection", "Algorithms: Greedy Coloring"])
+
+def plot_greedy_coloring(graph):
+    # Apply greedy coloring
+    graph_coloring = nx.greedy_color(graph)
+    unique_colors = set(graph_coloring.values())
+
+    # Assign colors to nodes based on the greedy coloring
+    graph_color_to_mpl_color = dict(zip(unique_colors, mpl.TABLEAU_COLORS))
+    node_colors = [graph_color_to_mpl_color[graph_coloring[n]] for n in graph.nodes()]
+
+    # Layout of the graph
+    pos = nx.spring_layout(graph, seed=14)
+
+    # Draw the graph
+    nx.draw(
+        graph,
+        pos,
+        with_labels=True,
+        node_size=500,
+        node_color=node_colors,
+        edge_color="grey",
+        font_size=12,
+        font_color="#333333",
+        width=2,
+    )
+
+    plt.title("Greedy Coloring of Graph")
+    st.pyplot(plt)
+
+def algorithms_greedy_coloring():
+    st.title("Algorithms: Greedy Coloring")
+
+    # Option to choose between creating your own or using the default example
+    graph_mode = st.radio(
+        "Choose a Mode:",
+        ("Default Example", "Create Your Own"),
+        help="The default example shows a predefined graph, or you can create your own."
+    )
+
+    if graph_mode == "Default Example":
+        # Create a predefined graph (Dodecahedral graph) for the greedy coloring example
+        G = nx.dodecahedral_graph()
+        st.write("Default Graph: Dodecahedral Graph with Greedy Coloring.")
+        plot_greedy_coloring(G)
+
+    elif graph_mode == "Create Your Own":
+        st.write("### Create Your Own Graph")
+
+        # Input for creating a custom graph
+        nodes_input = st.text_area("Enter nodes (e.g., 1, 2, 3, 4):")
+        edges_input = st.text_area("Enter edges (e.g., (1, 2), (2, 3), (3, 4)):").strip()
+
+        if st.button("Generate Graph"):
+            if nodes_input and edges_input:
+                try:
+                    # Parse the input for nodes and edges
+                    nodes = list(map(int, nodes_input.split(",")))
+                    edges = [tuple(map(int, edge.strip()[1:-1].split(","))) for edge in edges_input.split("),")]
+
+                    G = nx.Graph()
+                    G.add_nodes_from(nodes)
+                    G.add_edges_from(edges)
+
+                    st.write("Custom Graph:", G.edges())
+                    plot_greedy_coloring(G)
+
+                except Exception as e:
+                    st.error(f"Error creating the graph: {e}")
+            else:
+                st.error("Please enter valid nodes and edges.")
+
+if sidebar_option == "Algorithms: Greedy Coloring":
+    algorithms_greedy_coloring()
 
 # Helper function to draw and display graph
 def draw_graph(G, pos=None, title="Graph Visualization"):