move exercises, lecture examples, labs into subfolders

Lectures/LC21/use.c

@@ -0,0 +1,29 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#define BUILD1 23
+ 
+int main(void)
+{
+
+ int MyValue = 0;
+ 
+ printf ("\nThis code is common to all ");
+
+#ifdef BUILD1  
+
+ printf ("\nWe had BUILD1 defined, will adjust value accordingly  ");
+ MyValue = BUILD1;
+
+#else
+
+ printf ("\nBUILD1 was not defined, leaving MyValue alone ");
+
+#endif
+
+  printf  ("\nThe value in MyValue is %d ",MyValue);
+  printf ("\n\n");
+
+  return 0;
+
+}