diff --git a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/DijkstraAlgorithm.java b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/DijkstraAlgorithm.java
index 9bae6bd..0ea7fc9 100644
--- a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/DijkstraAlgorithm.java
+++ b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/shortestpath/DijkstraAlgorithm.java
@@ -17,7 +17,7 @@ public class DijkstraAlgorithm extends ShortestPathAlgorithm {
         super(data);
     }
 
-    final private boolean DEBUG = false;
+    final private boolean DEBUG = true;
 
     @Override
     protected ShortestPathSolution doRun() {
@@ -51,6 +51,7 @@ public class DijkstraAlgorithm extends ShortestPathAlgorithm {
 
             this.log("Cout marqué : " + parentLabel.getCost());
             this.log("Nb successeurs : " + parentNode.getNumberOfSuccessors());
+            this.log("tas valide : " + heap.isValid(0));
 
             for (Arc arc : parentNode.getSuccessors()) {
                 Label currentLabel = labels[arc.getDestination().getId()];
diff --git a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinaryHeap.java b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinaryHeap.java
index a21e211..8b28f73 100644
--- a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinaryHeap.java
+++ b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinaryHeap.java
@@ -188,6 +188,29 @@ public class BinaryHeap<E extends Comparable<E>> implements PriorityQueue<E> {
         return minItem;
     }
 
+    @Override
+    public boolean isValid(int index) {
+        if (this.currentSize <= index)
+            return true;
+
+        boolean valid = true;
+        E current = this.array.get(0);
+        int ileft = indexLeft(index);
+        int iright = ileft + 1;
+
+        if (ileft < this.currentSize) {
+            E left = this.array.get(ileft);
+            if (current.compareTo(left) < 0)
+                valid = this.isValid(ileft);
+        }
+        if (iright < this.currentSize) {
+            E right = this.array.get(iright);
+            if (current.compareTo(right) < 0)
+                valid = this.isValid(iright);
+        }
+        return valid;
+    }
+
     /**
      * Creates a multi-lines string representing a sorted view of this binary heap.
      *
diff --git a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinarySearchTree.java b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinarySearchTree.java
index 32dfbb1..2be6a8c 100644
--- a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinarySearchTree.java
+++ b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/BinarySearchTree.java
@@ -61,4 +61,10 @@ public class BinarySearchTree<E extends Comparable<E>> implements PriorityQueue<
         return min;
     }
 
+    @Override
+    public boolean isValid(int index) {
+        System.out.println("TODO implement isValid");
+        return false;
+    }
+
 }
diff --git a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/PriorityQueue.java b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/PriorityQueue.java
index 104f79e..5c807df 100644
--- a/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/PriorityQueue.java
+++ b/be-graphes-algos/src/main/java/org/insa/graphs/algorithm/utils/PriorityQueue.java
@@ -78,4 +78,11 @@ public interface PriorityQueue<E extends Comparable<E>> {
      */
     public E deleteMin() throws EmptyPriorityQueueException;
 
+    /**
+     * Checks if the current queue is valid
+     *
+     * @return If the queue is valid
+     */
+    public boolean isValid(int index);
+
 }