--- a/src/parallel_execution/examples/calc.cbc	Tue Apr 18 06:04:22 2017 +0900
+++ b/src/parallel_execution/examples/calc.cbc	Tue Apr 18 18:58:16 2017 +0900
@@ -2,6 +2,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <assert.h>
 
 #include "../../context.h"
 
@@ -212,6 +213,7 @@
 __code mult(struct Integer* input1, struct Integer* input2, struct Integer* output) { 
     output->value = input1->value * input2->value; 
     printf("%d * %d = %d\n", input1->value, input2->value, output->value); 
+    assert(output->value == 2 * (input2->value * input2->value) + input2->value);
     goto meta(context, context->next);
 }