There is a doubly linked list (double linked list?) In java. It creates a linkedList list = new linkedList() . It is filled with random int values, the length can be specified by the user. It is necessary to find the number of elements that are in the interval [-100; 100]. How to organize the cycle of searching for elements is more or less clear, but how to get the values ​​of the elements of the list in order to subsequently determine their belonging to the interval?

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    .get (i)? or even for (Integer u: list) or did I misunderstand the question? - pavel
  • When I enter .get (), the program complains that "method get () is undefined .." - Marqiz
  • and for works? get - yes, in the clean lists there is no, there is only an iterator to walk. - pavel
  • And how to write this for? Now I’m getting type mismatch - can't go - Marqiz
  • @Marqiz, add a code to whom you are trying to solve the problem - it will be easier to indicate where something is wrong - YuriySPb ♦

1 answer 1

 int count = 0; for (Object num : list) if ((Integer)num >= -100 && (Integer)num <= 100) count++; System.out.println("Всего элементов в заданном диапазоне: " + count); 
 int count = 0; for (int i=0; i<list.size(); i++) if ((Integer)list.get(i)>= -100 && (Integer)list.get(i) <= 100) count++; System.out.println("Всего элементов в заданном диапазоне: " + count);

No need to get them. It is in the map values ​​are stored inside Map.Entry , and here they are wrapped in nothing, they are as they are. Just your List not typed, it stores Object , which still need to be cast to the desired type. If you had a List<Integer> , then you would not need to perform a type conversion, and there would be no error.