diff --git a/README.md b/README.md
index 8d4a9a140737ffee08f74412b33843b7dc36ba6e..0a230d77d66c7f8bf851a96bbb390239fa089f7d 100644
--- a/README.md
+++ b/README.md
@@ -50,7 +50,7 @@ All examples are available in both C and Fortran90.
 - OpenMP Intro lab: 
   - [Instructions](intro_lab/README.md)
   - Simple hello world program [in C](intro_lab/hello.c) and [in Fortran](intro_lab/hello.f90)
-  - Calculate pi [in C](intro_lab/pi.c) and [in Fortran](intro_lab/pi.f90)
+  - Calculate π [in C](intro_lab/pi.c) and [in Fortran](intro_lab/pi.f90)
   - Solutions will be made available later during the lab
 - OpenMP Advanced Lab: 
   - [Instructions](advanced_lab/README.md)
diff --git a/intro_lab/hello.c b/intro_lab/hello.c
index 9cdc610c2107b6911af1be807e5b10adc727d59d..9e6f1fbfd74a3ad03b4d2f7143415de70d7a1a1c 100644
--- a/intro_lab/hello.c
+++ b/intro_lab/hello.c
@@ -1,8 +1,10 @@
 #include <stdio.h>
 
-int main ()
+int main()
 {
     int thread_id = 0;
 
     printf("Hello World from thread %d \n", thread_id);
+
+    return 0;
 }
diff --git a/intro_lab/pi.c b/intro_lab/pi.c
index 8bcfe7e134930e0bd1179742b4cc6e6db16437af..0d7bedb1db81185a91891f7947642d08e2aef6b3 100644
--- a/intro_lab/pi.c
+++ b/intro_lab/pi.c
@@ -20,7 +20,7 @@ History: Written by Tim Mattson, 11/99.
 static long num_steps = 100000000;
 double step;
 
-int main ()
+int main()
 {
     int i;
     double x, pi, sum = 0.0;
@@ -38,4 +38,6 @@ int main ()
     pi = step * sum;
     run_time = omp_get_wtime() - start_time;
     printf("\n pi with %ld steps is %lf in %lf seconds\n ",num_steps,pi,run_time);
+
+    return 0;
 }