Question

Suppose an ArrayList list contains {"red", "red", "green"}. What is the list after the following code? String element = "red"; for (int i = list.size() - 1; i >= 0; i--) if (list.get(i).equals(element)) list.remove(element);

Answer 1

The code provided is removing all occurrences of the string 'red' from the ArrayList 'list'. After running the code, the ArrayList 'list' will only contain the element 'green'.

Step-by-step explanation:

The original code provided would cause an error because it is trying to remove the element using list.remove(element); which will remove the first occurrence of the element by value, not the element at the specific index. Since we are iterating through the list backwards, to remove the current item at index i, we should modify the code to use the remove method that takes an index as an argument.

Here is the complete modified code that would work correctly for the given task:

for (int i = list.size() - 1; i >= 0; i--) {
if (list.get(i).equals(element)) {
list.remove(i);
}
}

After running the modified code on the ArrayList list with values {"red", "red", "green"}, the final list will be {"green"}, as both occurrences of "red" will be removed in the loop.

Answer 2

The output of the given code as follows:

Output:

{"red", "green"}

Step-by-step explanation:

• In the given code a list is defined, which contains three elements, which are "red, red, and green". In the next step, a string variable "element" is initialized with a value that is "red".

• Then a for loop is declared, that counts list size, and inside the loop and if block is declared, that compares the value list with element variable then it removes from the list.