New start/end constraint system

src/path/create/ilp.rs

@@ -71,6 +71,20 @@ pub fn solve<C: CreateContext>(ctx: C) -> C::Path {
         }
     }
 
+    // Respektiere Start- und Ende
+    let ends = [pool.ilp_start, pool.ilp_end].into_iter().flatten();
+    for start in ends {
+        let constraint = model.add_row();
+        model.set_row_upper(constraint, 1.0);
+        for j in node_indices() {
+            if j == start {
+                continue;
+            }
+            model.set_weight(constraint, x[start][j], 1.0);
+            model.set_weight(constraint, x[j][start], 1.0);
+        }
+    }
+
     // Jeder Knoten muss erreicht werden.
     for i in node_indices() {
         let mut pairs = Vec::new();
@@ -113,10 +127,10 @@ pub fn solve<C: CreateContext>(ctx: C) -> C::Path {
         }
     }
 
-    // Zyklen verhindern
-
     model.solve();
 
+    // Zyklen verhindern
+
     let mut paths = print_paths_solution(&mut model, &x);
 
     let time_start = Instant::now();
@@ -147,10 +161,17 @@ pub fn solve<C: CreateContext>(ctx: C) -> C::Path {
         paths = print_paths_solution(&mut model, &x);
     }
 
-    let path = &paths[0];
+    let mut path = paths[0].clone();
 
     // (matrix[(i, j)].into(), (0.0, 1.0));
 
+    if pool
+        .ilp_start
+        .is_some_and(|start| path.last() == Some(&start))
+    {
+        path.reverse();
+    }
+
     ctx.path_from_indices(path.iter().copied())
 }
 

src/pool.rs

@@ -12,4 +12,8 @@ pub struct OptionsPool {
     pub milp_solver: Option<MilpSolver>,
     #[serde(default)]
     pub ilp_max_duration: Option<u64>,
+    #[serde(default)]
+    pub ilp_start: Option<usize>,
+    #[serde(default)]
+    pub ilp_end: Option<usize>,
 }