diff --git a/src/main/java/jobshop/solvers/GreedySolver.java b/src/main/java/jobshop/solvers/GreedySolver.java
index f5bb180..1a6e755 100644
--- a/src/main/java/jobshop/solvers/GreedySolver.java
+++ b/src/main/java/jobshop/solvers/GreedySolver.java
@@ -51,8 +51,8 @@ public class GreedySolver implements Solver {
             case SPT:
                 return(
                     lTask.stream()
-                    .sorted(Comparator.comparing(e -> heuristiqueSPT(e, instance)))
-                    .toArray(Task[]::new)[0]
+                            .min(Comparator.comparing(e -> heuristiqueSPT(e, instance)))
+                            .get()
                 );
             case LRPT:
                 return(
@@ -65,8 +65,8 @@ public class GreedySolver implements Solver {
                 // find the minimal next execution time value
                 int EST_SPT_minValue = lTask.stream()
                                 .map(e -> heuristiqueEST(e, instance,machineStatus, jobStatus))
-                                .sorted()
-                                .toArray(Integer[]::new)[0];
+                                .min(Comparator.comparing(e -> e))
+                                .get();
 
                 // find all tasks with this next execution time value
                 Task[] EST_SPT_closestTasks = lTask.stream()
@@ -76,16 +76,16 @@ public class GreedySolver implements Solver {
                 // run SPT (see above) on this
                 return(
                         Arrays.stream(EST_SPT_closestTasks)
-                                .sorted(Comparator.comparing(e -> heuristiqueSPT(e, instance)))
-                                .toArray(Task[]::new)[0]
+                                .min(Comparator.comparing(e -> heuristiqueSPT(e, instance)))
+                                .get()
                 );
             case EST_LRPT:
 
                 // find the minimal next execution time value
                 int EST_LRPT_minValue = lTask.stream()
                         .map(e -> heuristiqueEST(e, instance,machineStatus, jobStatus))
-                        .sorted()
-                        .toArray(Integer[]::new)[0];
+                        .min(Comparator.comparing(e -> e))
+                        .get();
 
                 // find all tasks with this next execution time value
                 Task[] EST_LRPT_closestTasks = lTask.stream()