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@@ -189,6 +189,68 @@ module purge
 
 ## Compiling programs
 
+```
+#include <stdio.h>
+#include <mpi.h>
+
+int main (int argc, char *argv[])
+{
+	int id, np, i;
+	char processor_name[MPI_MAX_PROCESSOR_NAME];
+	int processor_name_len;
+
+	MPI_Init(&argc, &argv);
+
+	MPI_Comm_size(MPI_COMM_WORLD, &np);
+	MPI_Comm_rank(MPI_COMM_WORLD, &id);
+	MPI_Get_processor_name(processor_name, &processor_name_len);
+
+	for (i=1;i<2;i++)
+		printf ("Hello world from process %03d out of %03d, processor name %s \n", id, np, processor_name);
+
+	MPI_Finalize();
+	return 0;
+}
+```
+
+```
+#include "mpi.h"
+#include "string.h"
+#include <stdio.h>
+
+int main( int argc, char *argv[] )
+{
+	int numprocs, myrank, namelen, i;
+	char processor_name[MPI_MAX_PROCESSOR_NAME];
+	char greeting[MPI_MAX_PROCESSOR_NAME + 80];
+	MPI_Status status;
+
+	MPI_Init( &argc, &argv );
+	MPI_Comm_size( MPI_COMM_WORLD, &numprocs );
+	MPI_Comm_rank( MPI_COMM_WORLD, &myrank );
+	MPI_Get_processor_name( processor_name, &namelen );
+
+	sprintf( greeting, "Hello world, from process %d of %d on %s",
+		myrank, numprocs, processor_name );
+
+	if ( myrank == 0 ) {
+		printf( "%s\n", greeting );
+		for ( i = 1; i < numprocs; i++ ) {
+			MPI_Recv( greeting, sizeof( greeting ), MPI_CHAR,
+					i, 1, MPI_COMM_WORLD, &status );
+			printf( "%s\n", greeting );
+		}
+	}
+	else {
+		MPI_Send( greeting, strlen( greeting ) + 1, MPI_CHAR,
+				0, 1, MPI_COMM_WORLD );
+	}
+
+	MPI_Finalize( );
+	return 0;
+}
+```
+
 ## Submitting jobs
 
 ## More Slurm info
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