1 files changed, 5 insertions, 0 deletions
diff --git a/tabulator-mpi/main.cpp b/tabulator-mpi/main.cpp
index 959cd8c..cb60ecb 100644
--- a/tabulator-mpi/main.cpp
+++ b/tabulator-mpi/main.cpp
@@ -33,6 +33,11 @@ int main(int argc, char **argv) {
   MPI_Comm_rank(MPI_COMM_WORLD, &comm_rank);
   MPI_Comm_size(MPI_COMM_WORLD, &comm_size);
 
+  if (comm_size < 2) {
+    fprintf(stderr, "at least two processes are required\n");
+    return 1;
+  }
+
   const lib94::warrior **warriors = new const lib94::warrior *[argc - 1];
   for (int i = 0; i < argc - 1; ++i)
     warriors[i] = load_warrior(argv[i + 1]);