checkpoint 2025-08-22

tests/example_flows.rs

@@ -20,7 +20,7 @@ fn generate_small_maxflow_example() -> (StableGraph<(f32, f32), (u64, u64)>, Sta
     g.add_edge(one, two, (0,2));
     g.add_edge(two, four, (0,9));
     g.add_edge(three, t, (0,10));
-    g.add_edge(four, three, (0,6));
+    g.add_edge(four, three, (0,5)); // changed capacity to 5 to enforce a single optimal solution
     g.add_edge(four, t, (0,10));
 
     // TODO:
@@ -49,7 +49,7 @@ fn generate_small_maxflow_example() -> (StableGraph<(f32, f32), (u64, u64)>, Sta
     m.update_edge(one, two, (0,2));
     m.update_edge(two, four, (9,9));
     m.update_edge(three, t, (9,10));
-    m.update_edge(four, three, (5,6));
+    m.update_edge(four, three, (5,5)); // changed capacity to 5 to enforce a single optimal solution
     m.update_edge(four, t, (10,10));
 
     return (g, m, s, t);
@@ -57,11 +57,12 @@ fn generate_small_maxflow_example() -> (StableGraph<(f32, f32), (u64, u64)>, Sta
 
 fn graph_equal(one: StableGraph<(f32, f32), (u64, u64)>, other: StableGraph<(f32, f32), (u64, u64)>) -> bool {
     // ensure all edges have the same weights
-    println!("Graph 1: {:?}", one);
-    println!("Graph 2: {:?}", other);
     let edges = one.edge_indices().map(|e| e).collect::<Vec<_>>();
     for edge in edges {
         if one.edge_weight(edge).expect("edge index not found") != other.edge_weight(edge).expect("edge index not found") {
+            println!("Edge weights don't match");
+            println!("Graph 1: {:?}", one);
+            println!("Graph 2: {:?}", other);
             return false;
         }
     }
@@ -70,6 +71,9 @@ fn graph_equal(one: StableGraph<(f32, f32), (u64, u64)>, other: StableGraph<(f32
     let nodes = one.node_indices().map(|n| n).collect::<Vec<_>>();
     for node in nodes {
         if one.node_weight(node).expect("node index not found") != other.node_weight(node).expect("node index not found") {
+            println!("Node weights don't match");
+            println!("Graph 1: {:?}", one);
+            println!("Graph 2: {:?}", other);
             return false;
         }
     }
@@ -85,5 +89,38 @@ fn test_ford_fulkerson() {
     let mut  algo = FordFulkerson::from_problem(&problem);
     let solution = algo.run();
 
-    assert!(graph_equal(solution, m.residual()));
+    assert!(graph_equal(solution.prune_zero(), m.residual().prune_zero()));
+}
+
+#[test]
+fn test_edmonds_karp() {
+    let (g, m, s, t) = generate_small_maxflow_example();
+
+    let problem = MaxflowProblem::from(g, s, t);
+    let mut  algo = EdmondsKarp::from_problem(&problem);
+    let solution = algo.run();
+
+    assert!(graph_equal(solution.prune_zero(), m.residual().prune_zero()));
+}
+
+#[test]
+fn test_dinic() {
+    let (g, m, s, t) = generate_small_maxflow_example();
+
+    let problem = MaxflowProblem::from(g, s, t);
+    let mut  algo = Dinic::from_problem(&problem);
+    let solution = algo.run();
+
+    assert!(graph_equal(solution.prune_zero(), m.residual().prune_zero()));
+}
+
+#[test]
+fn test_goldberg_tarjan() {
+    let (g, m, s, t) = generate_small_maxflow_example();
+
+    let problem = MaxflowProblem::from(g, s, t);
+    let mut  algo = GoldbergTarjan::from_problem(&problem);
+    let solution = algo.run();
+
+    assert!(graph_equal(solution.prune_zero(), m.residual().prune_zero()));
 }