Run trivial heuristics before FJ

Author: BenChampion

highs/mip/HighsMipSolver.cpp

@@ -148,8 +148,19 @@ void HighsMipSolver::run() {
       mipdata_->queryExternalSolution(
           solution_objective_, kExternalMipSolutionQueryOriginAfterSetup);
 
+    // Apply the trivial heuristics
+    analysis_.mipTimerStart(kMipClockTrivialHeuristics);
+    HighsModelStatus returned_model_status = mipdata_->trivialHeuristics();
+    analysis_.mipTimerStop(kMipClockTrivialHeuristics);
+    if (modelstatus_ == HighsModelStatus::kNotset &&
+        returned_model_status == HighsModelStatus::kInfeasible) {
+      // trivialHeuristics can spot trivial infeasibility, so act on it
+      modelstatus_ = returned_model_status;
+      cleanupSolve();
+      return;
+    }
+    // Apply the feasibility jump heuristic (if enabled)
     if (options_mip_->mip_heuristic_run_feasibility_jump) {
-      // Apply the feasibility jump before evaluating the root node
       analysis_.mipTimerStart(kMipClockFeasibilityJump);
       HighsModelStatus returned_model_status = mipdata_->feasibilityJump();
       analysis_.mipTimerStop(kMipClockFeasibilityJump);
@@ -161,17 +172,7 @@ void HighsMipSolver::run() {
         return;
       }
     }
-    // Apply the trivial heuristics
-    analysis_.mipTimerStart(kMipClockTrivialHeuristics);
-    HighsModelStatus returned_model_status = mipdata_->trivialHeuristics();
-    analysis_.mipTimerStop(kMipClockTrivialHeuristics);
-    if (modelstatus_ == HighsModelStatus::kNotset &&
-        returned_model_status == HighsModelStatus::kInfeasible) {
-      // trivialHeuristics can spot trivial infeasibility, so act on it
-      modelstatus_ = returned_model_status;
-      cleanupSolve();
-      return;
-    }
+    // End of pre-root-node heuristics
     if (analysis_.analyse_mip_time && !submip)
       if (analysis_.analyse_mip_time & !submip)
         highsLogUser(options_mip_->log_options, HighsLogType::kInfo,