bugfix for cases where the minimum matlimit is reached

Author: JeroenGar

src/optimization/gdrr.rs

@@ -94,7 +94,8 @@ impl<'a> GDRR<'a> {
                 } else {
                     //Current local optimum is not better, add the best cost to the history queue
                     for _ in 0..(self.config.history_length - lahc_history.len()) {
-                        lahc_history.push_back(lahc_history.back().unwrap().clone());
+                        let best = lahc_history.back().unwrap_or(&empty_problem_cost).clone();
+                        lahc_history.push_back(best);
                     }
                 }
                 n_accepted += 1;
@@ -110,7 +111,7 @@ impl<'a> GDRR<'a> {
             }
             n_iterations += 1;
             if n_iterations % 100 == 0 {
-                self.local_sol_collector.rx_sync();
+                self.local_sol_collector.rx_sync()
             }
 
             debug_assert!(lahc_history.len() <= self.config.history_length, "{}", lahc_history.len());

src/optimization/instance.rs

@@ -57,6 +57,10 @@ impl Instance {
         }
     }
 
+    pub fn smallest_sheet_value(&self) -> u64 {
+        self.sheets.iter().map(|(s, _)| s.area()).min().unwrap()
+    }
+
     pub fn total_part_area(&self) -> u64 {
         self.total_part_area
     }

src/optimization/sol_collectors/global_sol_collector.rs

@@ -82,6 +82,11 @@ impl GlobalSolCollector {
                     }
                 }
             }
+            if self.material_limit.unwrap_or(u64::MAX) == self._instance.smallest_sheet_value(){
+                timed_println!("Minimum material limit reached");
+                break;
+            }
+
             if gdrr_thread_handlers.iter().all(|h| h.is_finished()) {
                 timed_println!("All GDRR threads have finished execution");
                 break;

src/optimization/sol_collectors/local_sol_collector.rs

@@ -21,7 +21,6 @@ pub struct LocalSolCollector<'a> {
     best_complete_transferred: bool,
     best_incomplete_transferred: bool,
     terminate: bool,
-
 }
 
 
@@ -161,7 +160,6 @@ impl<'a> LocalSolCollector<'a> {
         self.material_limit.unwrap_or(u64::MAX)
     }
 
-
     pub fn terminate(&self) -> bool {
         self.terminate
     }