Merge pull request #65 from sadeem-albir/patch-4

Update variables.c

chapter_4/exercise_4_06/variables.c

@@ -244,7 +244,7 @@ int getop(char s[])
 
   s[1] = '\0';
 
-  if (isalpha(c) && !(c >= 'A' && c <= 'Z'))
+  if (islower(c))
   {
     var = c;
     return VARGET;
@@ -296,7 +296,3 @@ int getop(char s[])
 
   return NUMBER;
 }
-/* To prevent the variable checking in getop() from overlapping with the letter commands,
-make sure you set the commands to capital letters and explicitly tell the getop() to only
-check for variable-getting if the character is not capital
-e.g insteat of "if (isalpha(c))" you add "if (isalpha(c) && !(c >= 'A' && c >= 'Z'))"*/