diff --git a/llo-index.yml b/llo-index.yml
new file mode 100644
index 0000000..b07b12f
--- /dev/null
+++ b/llo-index.yml
@@ -0,0 +1,50 @@
+--- # Programming language
+  name: "mpi"
+  language: "c"
+  created-at: "21-07-2020"
+  creator: "root Apostolos"
+  git_url: "https://git.swarmlab.io:3000/labs/examples-mpi2.git"
+  base_dir: "examples-mpi2"
+  llospec0:
+    display_name: "title"
+    dir: "llo"
+    swarmlabservice: "os2"
+    info:
+      subdir: ""
+      asciidoc: "adoc"
+      file: "nmap.adoc"
+      mimetype: "text/x-python"
+    code:
+      subdir: ""
+      lang: "c"
+      version: "2"
+      file: "squares.c"
+      options: ""
+      mimetype: "text/plain"
+    challenge:
+      subdir: ""
+      question: "q-info.sh"
+      codehelp: "codehelp.sh"
+      codeanswer: "codeanswer.sh"
+      points: "1" # ELO
+      mimetype: "text/x-python"
+  llospec1:
+    display_name: "title1"
+    dir: "net1"
+    swarmlabservice: "os21"
+    info:
+      asciidoc: "adoc1"
+      file: "nmap.adoc1"
+      mimetype: "text/x-python"
+    code:
+      lang: "bash1"
+      version: "21"
+      file: "nmap.sh1"
+      options: " -c "
+      mimetype: "text/x-python"
+    challenge:
+      question: "q-info.sh1"
+      codehelp: "codehelp.sh1"
+      codeanswer: "codeanswer.sh1"
+      points: "1" # ELO
+      mimetype: "text/x-python"
diff --git a/swarmlab/llo/squares.c b/swarmlab/llo/squares.c
new file mode 100644
index 0000000..e37fcea
--- /dev/null
+++ b/swarmlab/llo/squares.c
@@ -0,0 +1,60 @@
+#include <stdio.h>
+#include "mpi.h"
+
+main(int argc, char** argv)  
+{
+   int my_rank;
+   int p,k,res,finres,num;
+   int source,target;
+   int tag1=50, tag2=60, tag3=70;
+   int plithos;
+   int data[100];
+   int data_loc[100];
+   MPI_Status status;
+
+   MPI_Init(&argc, &argv);
+   MPI_Comm_rank(MPI_COMM_WORLD, &my_rank);
+   MPI_Comm_size(MPI_COMM_WORLD, &p);
+
+   if (my_rank == 0)  {
+       printf("Dose plithos aritmon:\n");
+       scanf("%d", &plithos);
+       printf("Dose tous %d arithmous:\n", plithos); 
+       for (k=0; k<plithos; k++)
+            scanf("%d", &data[k]);
+       for (target = 1; target < p; target++) 
+           MPI_Send(&plithos, 1, MPI_INT, target, tag1, MPI_COMM_WORLD);
+      num = plithos/p;  k=num;
+      for (target = 1; target < p; target++)  {
+         MPI_Send(&data[k], num, MPI_INT, target, tag2, MPI_COMM_WORLD);
+         k+=num;  }
+      for (k=0; k<num; k++)
+         data_loc[k]=data[k];
+     }
+   else  {
+       MPI_Recv(&plithos, 1, MPI_INT, 0, tag1, MPI_COMM_WORLD, &status);
+       num = plithos/p;
+       MPI_Recv(&data_loc[0], num, MPI_INT, 0, tag2, MPI_COMM_WORLD, &status);
+     }
+
+   res = 0;
+   for (k=0; k<num; k++)
+        res = res + (data_loc[k]*data_loc[k]);
+
+   if (my_rank != 0)  {
+       MPI_Send(&res, 1, MPI_INT, 0, tag3, MPI_COMM_WORLD);
+    }
+   else  {
+       finres = res;
+       printf("\n Apotelesma of process %d: %d\n", my_rank, res);
+       for (source = 1; source < p; source++)  {
+           MPI_Recv(&res, 1, MPI_INT, source, tag3, MPI_COMM_WORLD, &status);
+           finres = finres + res;
+           printf("\n Apotelesma of process %d: %d\n", source, res);
+        }
+    printf("\n\n\n Teliko Apotelesma: %d\n", finres);
+   }
+
+   MPI_Finalize();
+} 
+