diff --git a/.classpath b/.classpath
index c70d51a..348ad9a 100644
--- a/.classpath
+++ b/.classpath
@@ -2,5 +2,6 @@
 <classpath>
 	<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
 	<classpathentry kind="src" path="Axel/src"/>
+	<classpathentry kind="con" path="org.eclipse.jdt.junit.JUNIT_CONTAINER/5"/>
 	<classpathentry kind="output" path="bin"/>
 </classpath>
diff --git a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Axel.java b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Axel.java
index 450705c..3eaae7c 100644
--- a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Axel.java
+++ b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Axel.java
@@ -20,11 +20,11 @@ public class Axel {
 		cols=Integer.parseInt(kb.nextLine());
 		Spreadsheet spr=new Spreadsheet(rows,cols);
 		//spr.put("A3", "3");
-		//spr.put("A2", "1");
-		
-		//spr.put("B9", "=41+A2");
-		//spr.put("J5", "=7*6");
-		//spr.put("J6", "=3/2");
+		spr.put("A2", "2");
+		spr.put("A1","=19+4");
+		spr.put("B9", "=41+A2");
+		spr.put("J5", "=7*6");
+		spr.put("J6", "=4/2");
 		
 		while(true) {
 			System.out.println(spr);
@@ -44,8 +44,6 @@ public class Axel {
 		}
 		spr.saveCsv("/tmp/test.csv");
 		kb.close();
-		
-		// TODO: You might want to put "UI loop" for entering value and formulas here resp. in some UI methods.
 	}
 
 }
\ No newline at end of file
diff --git a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
index c077ec1..847bed2 100644
--- a/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
+++ b/Axel/src/de/hs_mannheim/informatik/spreadsheet/Spreadsheet.java
@@ -21,15 +21,13 @@ public class Spreadsheet {
 	 * @param cols number of columns
 	 */
 	public Spreadsheet(int rows, int cols) {
-		
-		// TODO limit the maximum size on 99 (1..99) rows and 26 (A..Z) columns
 		if (rows>99){
 			rows=99;
 		}
 		if (cols>26) {
 			cols=26;
 		}
-		
+
 		cells = new Cell[rows][cols];
 
 		for (int r = 0; r < rows; r++)
@@ -260,14 +258,59 @@ public class Spreadsheet {
 		Matcher m = Pattern.compile("([A-Z][0-9]*)|[-\\+\\*/]|[0-9]*").matcher(formula);
 
 		long res = 0;
+		boolean first=true;
+		String operation="";
 
-		// TODO implement
-
-		// uncomment the following to see an example how the elements of a formula can be accessed
 		while (m.find()) {        // m.find() must always be used before m.group()
 			String s = m.group();
-			if (!s.isEmpty()) {
-				System.out.println(s);
+			if(!s.isEmpty()) {
+				if(first && (int)s.charAt(0)>=(int)'A'&&(int)s.charAt(0)<=(int)'Z') {
+					res=Integer.parseInt(cells[(Integer.parseInt(s.substring(1)))-1][(int)s.charAt(0)-(int)-'A'].getValue());
+					first=false;
+				}else if(first) {
+					res=Integer.parseInt(s);
+					first=false;
+				}else if(s.equals("+")){
+					operation="+";
+				}else if(s.equals("-")){
+					operation="-";
+				}else if(s.equals("*")){
+					operation="*";
+				}else if(s.equals("/")){
+					operation="/";
+				}else if((int)s.charAt(0)>=(int)'A'&&(int)s.charAt(0)<=(int)'Z'){
+					switch(operation) {
+					case("+"):
+						res+=Integer.parseInt(cells[(Integer.parseInt(s.substring(1)))-1][(int)s.charAt(0)-(int)'A'].getValue());
+						break;
+					case("-"):
+						res-=Integer.parseInt(cells[(Integer.parseInt(s.substring(1)))-1][(int)s.charAt(0)-(int)'A'].getValue());
+						break;
+					case("*"):
+						res*=Integer.parseInt(cells[(Integer.parseInt(s.substring(1)))-1][(int)s.charAt(0)-(int)'A'].getValue());
+						break;
+					case("/"):
+						res/=Integer.parseInt(cells[(Integer.parseInt(s.substring(1)))-1][(int)s.charAt(0)-(int)'A'].getValue());
+						break;
+					}
+				}else {
+					switch(operation) {
+					case("+"):
+						res+=Integer.parseInt(s);
+						break;
+					case("-"):
+						res-=Integer.parseInt(s);
+						break;
+					case("*"):
+						res*=Integer.parseInt(s);
+						break;
+					case("/"):
+						res/=Integer.parseInt(s);
+						break;
+					}
+				}
+
+
 			}
 		}