Merge pull request #2 from Specy/branch&bound

Branch&bound, fixes #1

examples/tsp.rs

@@ -533,7 +533,7 @@ fn find_min_cut(size: usize, weights: &mut [f64]) -> (f64, Vec<bool>) {
     }
 
     assert!(best_cut_weight.is_finite());
-    return (best_cut_weight, best_cut);
+    (best_cut_weight, best_cut)
 }
 
 #[cfg(test)]

src/broken_tests.rs

@@ -0,0 +1,32 @@
+mod broken_tests {
+    use crate::{ComparisonOp, OptimizationDirection, Problem};
+
+    #[test]
+    #[should_panic]
+    fn broken_test_1() {
+        let mut problem = Problem::new(OptimizationDirection::Maximize);
+
+        // Define variables with their objective coefficients
+        let x = problem.add_var(50.0, (2.0, f64::INFINITY));
+        let y = problem.add_var(40.0, (0.0, 7.0)); 
+
+        //TODO this fails to find optimal solution with f64::MAX
+        let z = problem.add_var(45.0, (0.0, f64::MAX));
+
+
+        problem.add_constraint(&[(x, 3.0), (y, 2.0), (z, 1.0)], ComparisonOp::Le, 20.0);
+        problem.add_constraint(&[(x, 2.0), (y, 1.0), (z, 3.0)], ComparisonOp::Le, 15.0);
+
+        let sol = problem.solve().unwrap();
+
+        assert_eq!(
+            [
+                *sol.var_value(x),
+                *sol.var_value(y),
+                *sol.var_value(z)
+            ],
+            [2.0, 6.2, 1.6]
+        );
+        assert_eq!(sol.objective(), 420.0);
+    }
+}