fixed failing issues with lesson select function

cmdtypist.c

@@ -21,5 +21,23 @@ void select_lesson(int argc_cmd)
 				while(ch=getchar()!='\n');//disposing off wrong input string.
 			}
 		}
-
+		else
+		{
+			fprintf(stderr, "%s\n", "Invalid number of arguments, consult \"cmdtypist --help\" for more");
+			exit(EXIT_FAILURE);
+		}
+			/*
+			if(argc_cmd==3)
+				if(strncmp(argv[2],"select",6)!=0||lesson_choice<1||lesson_choice>20)
+				{
+					fprintf(stderr, "%s\n", "Command not found\n");
+					if(strncmp(argv[2],"se",2))
+						fprintf(stderr, "%s\n", "Did you mean \"select\"");
+					else if(lesson_choice<1||lesson_choice>20)
+						fprintf(stderr, "%s %d\n", "No lesson entry for ",lesson_choice);
+					//else if(ch!=1)
+				        printf("%s", "Lesson number cannot contain symbols or alpha letters.\n");
+					exit(EXIT_FAILURE);
+				}*/
+		printf("\n");
 	}