text: /* 
  ------------------------------------------------------------------------------------
   Tutorial: Skipping iterations - continue instruction
  ------------------------------------------------------------------------------------
  */
  
  /* Loop optimalization
  Some actions in loop doesn't need to be done every iteration
  You can escape loop iteration in middle of it. 
  
  Let's add all strings to make sentence. 
  */
  
  // Imagine very long array
  let arr = [
      'hello',
      42,
      108,
      'number',
      "world"
  ];
  
  let output = ""; //Set temporary variable
  
  for(let i = 0; i < arr.length; i++){ //Iterates trought whole array
      if(typeof arr[i] != String) //If current element isn't string, we can skip processing
  		continue; 
      
      /* 
      ...here may be heavy code... 
      */
  
      output += arr[i].toLowerCase() + " "; //
  }
  
  console.log(output); // Will print "hello number world", all nubers are skipped, and processing time is short
  /*
  ------------------------------------------------------------------------------------
   Challenge: create script that adds every cube of squere roots of numbers form array [2, 'car', 3, "cat", 81, true, 9]
  ------------------------------------------------------------------------------------
  */