diff --git a/src/parallel.c b/src/parallel.c
index cd7548e..5d0430c 100644
--- a/src/parallel.c
+++ b/src/parallel.c
@@ -130,15 +130,17 @@ void find_end(int residue, char *pattern, char *text, int **matches, int *match_
 void search_for_splitted_pattern(int *residue, int *match_number, int **matches) {
     // send the residue to the next process
     if (rank + 1 != size) {
-        MPI_Send(residue, 1, MPI_INT, rank + 1, DEFAULT_TAG, MPI_COMM_WORLD);
+        MPI_Request request;
+        MPI_Isend(residue, 1, MPI_INT, rank + 1, DEFAULT_TAG, MPI_COMM_WORLD, &request);
     }
 
     // receiving the residue from the previous process
+    int other_residue = 0;
     if (rank != 0) {
-        MPI_Recv(residue, 1, MPI_INT, rank - 1, DEFAULT_TAG, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
-        if (*residue != 0)
+        MPI_Recv(&other_residue, 1, MPI_INT, rank - 1, DEFAULT_TAG, MPI_COMM_WORLD, MPI_STATUS_IGNORE);
+        if (other_residue != 0)
             // search for a split match
-            find_end(*residue, pattern, private_text, matches, match_number);
+            find_end(other_residue, pattern, private_text, matches, match_number);
     }
 
 }