diff --git a/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.cpp b/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.cpp
index 65976ea..e4c0100 100644
--- a/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.cpp
+++ b/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.cpp
@@ -1,7 +1,3 @@
-//
-// Created by mpapa on 05.12.2017.
-//
-
 #include "AbstractionLayer_1.h"
 #include "../../../header.h"
 #include <iostream>
@@ -13,6 +9,7 @@ bool AbstractionLayer_1::PreProcessing(coor mySize,  const vector<Part*>* partAr
     const vector<Part*>& ref_partArray = *partArray;
     analyseParts analyse(mySize.row*mySize.col);
     Part buf;
+    int PSum=0;
     int iterator=0;
     if(!analyse.getImages())
     {
@@ -23,7 +20,8 @@ bool AbstractionLayer_1::PreProcessing(coor mySize,  const vector<Part*>* partAr
         //TODO rows and cols
         for(int i = 0; i < mySize.row*mySize.col; i++)
         {
-            unsigned char poempel = analyse.getTabs(i);;
+            unsigned char poempel = analyse.getTabs(i);
+            PSum+=PoempelSum(poempel); //preprocess correct check
             for (int j=0;j<4;j++)
             {
                 ref_partArray[iterator]->m_a1.m_connections=poempel;
@@ -32,10 +30,12 @@ bool AbstractionLayer_1::PreProcessing(coor mySize,  const vector<Part*>* partAr
             }
         }
 
+    if(PREPRO_CHECK && PSum)
+        return false;
+
+
     //Zugriff auf den vector mit den einzelnen teilen: part[0].getConnenctions() entspricht pömpel von bild 0.jpg und liefert ein unsigned char, poempl Belegung wie ausgemacht
 
-
-
     InitialiseConstraintMatrixSize(mySize.col+2, mySize.row+2); //col row switched in this function
     setEdgeZero();
 
@@ -43,6 +43,33 @@ bool AbstractionLayer_1::PreProcessing(coor mySize,  const vector<Part*>* partAr
     return true;
 }
 
+int AbstractionLayer_1::PoempelSum(uint8_t constraint)
+{
+    int PoempelSum=0;
+    if((constraint & 0b11000000)==0b01000000)
+        PoempelSum--;
+    else if((constraint & 0b11000000)==0b10000000)
+        PoempelSum++;
+
+    if((constraint & 0b00110000)==0b00010000)
+        PoempelSum--;
+    else if((constraint & 0b00110000)==0b00100000)
+        PoempelSum++;
+
+    if((constraint & 0b00001100)==0b00000100)
+        PoempelSum--;
+    else if((constraint & 0b00001100)==0b00001000)
+        PoempelSum++;
+
+    if((constraint & 0b00000011)==0b00000001)
+        PoempelSum--;
+    else if((constraint & 0b00000011)==0b00000010)
+        PoempelSum++;
+
+    return PoempelSum;
+
+}
+
 //it through qualityVector and removes all that do not trigger PlaceOfPartGood
 bool AbstractionLayer_1::EvaluateQuality (const coor constraintCoordinate, qualityVector& qVector)
 {
diff --git a/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.h b/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.h
index 15a49b8..42189c8 100644
--- a/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.h
+++ b/Source/functions/AbstractionLayers/Layer1/AbstractionLayer_1.h
@@ -55,6 +55,7 @@ public:
     void shift(uint8_t& Part, int shifts);
     void setEdgeZero();
 
+    int PoempelSum(uint8_t constraint);
 
     void CreateRandomPuzzle();
     qualityVector returnInBox(vector<Part>& PuzzleBox);
diff --git a/Source/functions/solve/puzzleExtension.cpp b/Source/functions/solve/puzzleExtension.cpp
index 7037108..82a9c64 100644
--- a/Source/functions/solve/puzzleExtension.cpp
+++ b/Source/functions/solve/puzzleExtension.cpp
@@ -1,6 +1,3 @@
-//
-// Created by Raphael Maenle on 21/12/2017.
-//
 #include "../../header/solve.h"
 #include "../../header/input.h"
 
diff --git a/Source/header.h b/Source/header.h
index 533aff6..bcf9329 100755
--- a/Source/header.h
+++ b/Source/header.h
@@ -7,6 +7,7 @@
 #include <algorithm>
 #include <random>
 
+#define PREPRO_CHECK false
 using namespace std;
 
 #include "header/input.h"
diff --git a/Source/header/solve.h b/Source/header/solve.h
index c0a48ca..08485f3 100755
--- a/Source/header/solve.h
+++ b/Source/header/solve.h
@@ -44,8 +44,9 @@ public:
     bool PreProcessing()
     {
         createBox(); createp_box();
-        dp.PreProcessing({cols,rows}, nullptr);
-        a1.PreProcessing({cols,rows}, &p_myBox);
+        if(!dp.PreProcessing({cols,rows}, nullptr))  return false;
+        if(!a1.PreProcessing({cols,rows}, &p_myBox)) return false;
+
         return true;
     }