fix: refactor and fix code

Author: adamcegielka

01_basics/01-output.js

@@ -4,7 +4,6 @@ console.log('JavaScript Output + html file');
 console.log('Hello World!'); // Hello World!
 console.log(4 + 6); // 10
 console.log('First Name', 'Age:', 45); // First Name Age: 45
-console.log('First Name' + 'Age:' + 45); // First Name Age: 45
 
 console.log('Hello! \nGood How are you today?'); // \n - from a new line
 
@@ -17,12 +16,7 @@ console.log(`Lorem ipsum dolor sit amet, consectetur adipiscing elit.
             ad litora torquent per conubia nostra, per inceptos himenaeos.`);
 
 // innerHTML
-document.getElementById('id_name').innerHTML = 'Addition result: ' + (3 + 4); // Addition result: 7
-
-let elements = document.getElementsByClassName('class_name'); //Subtraction result: 6
-for (var i = 0; i < elements.length; i++) {
-  elements[i].innerHTML = 'Subtraction result: ' + (10 - 4);
-}
+document.getElementById('id_name').innerHTML = 3 + 4;
 
 // write()
 document.write(8 + 9);