diff --git a/genomix/genomix-pregelix/src/main/java/edu/uci/ics/genomix/pregelix/operator/tipremove/TipAddVertex.java b/genomix/genomix-pregelix/src/main/java/edu/uci/ics/genomix/pregelix/operator/tipremove/TipAddVertex.java
index 519ffb9..8e77a0a 100644
--- a/genomix/genomix-pregelix/src/main/java/edu/uci/ics/genomix/pregelix/operator/tipremove/TipAddVertex.java
+++ b/genomix/genomix-pregelix/src/main/java/edu/uci/ics/genomix/pregelix/operator/tipremove/TipAddVertex.java
@@ -4,11 +4,10 @@
 import org.apache.hadoop.io.NullWritable;
 
 import edu.uci.ics.genomix.type.KmerBytesWritable;
+import edu.uci.ics.genomix.type.KmerListWritable;
 import edu.uci.ics.pregelix.api.graph.Vertex;
 import edu.uci.ics.pregelix.api.job.PregelixJob;
 import edu.uci.ics.pregelix.api.util.BspUtils;
-import edu.uci.ics.genomix.oldtype.PositionListWritable;
-import edu.uci.ics.genomix.oldtype.PositionWritable;
 import edu.uci.ics.genomix.pregelix.client.Client;
 import edu.uci.ics.genomix.pregelix.format.GraphCleanInputFormat;
 import edu.uci.ics.genomix.pregelix.format.GraphCleanOutputFormat;
@@ -47,7 +46,7 @@
  *  Remove tip or single node when l > constant
  */
 public class TipAddVertex extends
-        Vertex<PositionWritable, VertexValueWritable, NullWritable, MessageWritable> {
+        Vertex<KmerBytesWritable, VertexValueWritable, NullWritable, MessageWritable> {
     public static final String KMER_SIZE = "TipAddVertex.kmerSize";
     public static int kmerSize = -1;
    
@@ -58,37 +57,39 @@
         if (kmerSize == -1)
             kmerSize = getContext().getConfiguration().getInt(KMER_SIZE, 5);
     }
-
+    
+    /**
+     * create a new vertex point to split node
+     */
+    
     @SuppressWarnings("unchecked")
     @Override
     public void compute(Iterator<MessageWritable> msgIterator) {
         initVertex(); 
         if(getSuperstep() == 1){
-            if(getVertexId().getReadID() == 1 && getVertexId().getPosInRead() == 4){
-                getVertexValue().getFFList().append(2, (byte)1);
+            if(getVertexId().toString().equals("CTA")){
+                KmerBytesWritable vertexId = new KmerBytesWritable(kmerSize);
+                vertexId.setByRead("AGC".getBytes(), 0);
+                getVertexValue().getRFList().append(vertexId);
                 
                 //add tip vertex
                 @SuppressWarnings("rawtypes")
                 Vertex vertex = (Vertex) BspUtils.createVertex(getContext().getConfiguration());
                 vertex.getMsgList().clear();
                 vertex.getEdges().clear();
-                PositionWritable vertexId = new PositionWritable();
-                VertexValueWritable vertexValue = new VertexValueWritable();
+                
+                VertexValueWritable vertexValue = new VertexValueWritable(kmerSize);
                 /**
                  * set the src vertex id
                  */
-                vertexId.set(2, (byte)1);
                 vertex.setVertexId(vertexId);
                 /**
                  * set the vertex value
                  */
-                byte[] array = { 'G', 'A', 'A'};
-                KmerBytesWritable kmer = new KmerBytesWritable(array.length);
-                kmer.setByRead(array, 0);
-                vertexValue.setKmer(kmer);
-                PositionListWritable plist = new PositionListWritable();
-                plist.append(new PositionWritable(1, (byte)4));
-                vertexValue.setRRList(plist);
+                KmerListWritable kmerList = new KmerListWritable(kmerSize);
+                kmerList.append(vertexId);
+                vertexValue.setRFList(kmerList);
+                vertexValue.setKmer(vertexId);
                 vertex.setVertexValue(vertexValue);
                 
                 addVertex(vertexId, vertex);
@@ -106,7 +107,7 @@
         job.setVertexInputFormatClass(GraphCleanInputFormat.class);
         job.setVertexOutputFormatClass(GraphCleanOutputFormat.class);
         job.setDynamicVertexValueSize(true);
-        job.setOutputKeyClass(PositionWritable.class);
+        job.setOutputKeyClass(KmerBytesWritable.class);
         job.setOutputValueClass(VertexValueWritable.class);
         Client.run(args, job);
     }
diff --git a/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobGen/JobGenerator.java b/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobGen/JobGenerator.java
index 630b5aa..4648bc0 100644
--- a/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobGen/JobGenerator.java
+++ b/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobGen/JobGenerator.java
@@ -128,22 +128,22 @@
     private static void genSplitRepeatGraph() throws IOException {
         generateSplitRepeatGraphJob("SplitRepeatGraph", outputBase + "SplitRepeatGraph.xml");
     }
-//    private static void generateTipAddGraphJob(String jobName, String outputPath) throws IOException {
-//        PregelixJob job = new PregelixJob(jobName);
-//        job.setVertexClass(TipAddVertex.class);
-//        job.setVertexInputFormatClass(GraphCleanOutputFormat.class);
-//        job.setVertexOutputFormatClass(GraphCleanOutputFormat.class);
-//        job.setDynamicVertexValueSize(true);
-//        job.setOutputKeyClass(PositionWritable.class);
-//        job.setOutputValueClass(VertexValueWritable.class);
-//        job.getConfiguration().setInt(TipAddVertex.KMER_SIZE, 3);
-//        job.getConfiguration().writeXml(new FileOutputStream(new File(outputPath)));
-//    }
-//
-//    private static void genTipAddGraph() throws IOException {
-//        generateTipAddGraphJob("TipAddGraph", outputBase
-//                + "TipAddGraph.xml");
-//    }
+    private static void generateTipAddGraphJob(String jobName, String outputPath) throws IOException {
+        PregelixJob job = new PregelixJob(jobName);
+        job.setVertexClass(TipAddVertex.class);
+        job.setVertexInputFormatClass(InitialGraphCleanInputFormat.class);
+        job.setVertexOutputFormatClass(GraphCleanOutputFormat.class);
+        job.setDynamicVertexValueSize(true);
+        job.setOutputKeyClass(KmerBytesWritable.class);
+        job.setOutputValueClass(VertexValueWritable.class);
+        job.getConfiguration().setInt(TipAddVertex.KMER_SIZE, 3);
+        job.getConfiguration().writeXml(new FileOutputStream(new File(outputPath)));
+    }
+
+    private static void genTipAddGraph() throws IOException {
+        generateTipAddGraphJob("TipAddGraph", outputBase
+                + "TipAddGraph.xml");
+    }
 //    
 //    private static void generateTipRemoveGraphJob(String jobName, String outputPath) throws IOException {
 //        PregelixJob job = new PregelixJob(jobName);
@@ -243,6 +243,7 @@
 //        genP4ForMergeGraph();
 //        genMapReduceGraph();
         genSplitRepeatGraph();
+        genTipAddGraph();
     }
 
 }
diff --git a/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobRun/TipAddSmallTestSuite.java b/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobRun/TipAddSmallTestSuite.java
index f4456ce..57f4ea5 100644
--- a/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobRun/TipAddSmallTestSuite.java
+++ b/genomix/genomix-pregelix/src/test/java/edu/uci/ics/genomix/pregelix/JobRun/TipAddSmallTestSuite.java
@@ -43,20 +43,9 @@
 public class TipAddSmallTestSuite extends TestSuite {
     private static final Logger LOGGER = Logger.getLogger(TipAddSmallTestSuite.class.getName());
 
-    public static final String PreFix = "data/input"; //"graphbuildresult";
+    public static final String PreFix = "data/PathMergeTestSet"; //"graphbuildresult";
     public static final String[] TestDir = { PreFix + File.separator
-    + "read"};/*, PreFix + File.separator
-            /*+ "CyclePath"};, PreFix + File.separator
-            + "SimplePath", PreFix + File.separator
-            + "SinglePath", PreFix + File.separator
-            + "TreePath"};*/
-           /* + "2", PreFix + File.separator + "3", PreFix + File.separator + "4", PreFix + File.separator + "5",
-            PreFix + File.separator + "6", PreFix + File.separator + "7", PreFix + File.separator + "8",
-            PreFix + File.separator + "9", PreFix + File.separator + "TwoKmer", PreFix + File.separator + "ThreeKmer",
-            PreFix + File.separator + "SinglePath", PreFix + File.separator + "SimplePath",
-            PreFix + File.separator + "Path", PreFix + File.separator + "BridgePath",
-            PreFix + File.separator + "CyclePath", PreFix + File.separator + "RingPath",
-            PreFix + File.separator + "LongPath", PreFix + File.separator + "TreePath" };*/
+    + "5"};
     private static final String ACTUAL_RESULT_DIR = "data/actual/tipadd";
     private static final String PATH_TO_HADOOP_CONF = "src/test/resources/hadoop/conf";
     private static final String PATH_TO_CLUSTER_STORE = "src/test/resources/cluster/stores.properties";