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Modification or change in the collection’s elements while iterating or traversing through
                  that collection is not allowed and it will throw an error.

                  So, unmodifiable collection are those collections which  do not support modification
                  operations (add, remove and clear). Collections are immutable if there will be no change in

                  the collection object. Lists are of fixed size, if they assure that their size remains constant
                  only the elements can change in it. Lists are of variable-size also. You cannot iterate or
                  modify a null collection.

                  Adding elements to collection during iteration

                  To add elements while iterating or traversing a list, set or map, the new elements are kept
                  in a temporary list, set, or map and then the elements are added once you finish traversing
                  or iterating the collection.


                  Removing elements from collection during iteration
                  To remove elements from a list, you can create a new list, then add or insert the elements you
                  wish to keep. Or, you can also insert or add the elements you wish to remove to a different

                  list and then remove the elements after you finish the traversing or iterating the collection.
                  to remove to a different list and remove them after you finish iterating the collection.

                    Coding           uiz   02                                                          Critical Thinking



                      Give one-word answer to the following questions.

                      a.  Name the collection which stores similar data type variable.             ...........................

                      b.  What is the list called whose size remain constant.                      ...........................





                        At a Glance
                        Collections are used to store data and you can also retrieve and manipulate data stored in
                        the Collections.

                        Arrays do not support different data types.
                        Collections consist of lists, sets, or maps.
                        Modifying a collection's elements while iterating through that collection is not allowed and
                        it will throws an error in the program.

                        To add elements while iterating a list, set or map, keep the new elements in a temporary
                        list, set, or map and then add them to the original once you finish iterating the collection.







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