diff --git a/omp/src/main.c b/omp/src/main.c
index 2134fa5..46f15be 100644
--- a/omp/src/main.c
+++ b/omp/src/main.c
@@ -19,7 +19,7 @@ print_time_diff (struct timespec *start, struct timespec *end)
       nsec += 1000000000;
     }
 
-  printf ("Elapsed time: %ld.%09ld sec\n", sec, nsec);
+  printf ("Elapsed time: %ld.%09lds\n", sec, nsec);
 }
 
 void