ArrayList Practice Worksheet - Insert and Remove Operations

For each question, show what the ArrayList contains after performing all the given operations in order. Write out each step to get full credit.

Question 1

Start with an empty ArrayList called `words`. Perform these operations:

1. words.add("cat")
2. words.add("dog")
3. words.add(1, "bird")
4. words.remove(0)
5. words.add("fish")
6. words.remove("bird")

Show the final contents of the ArrayList:

Final answer: [______, ______]

Question 2

Start with an ArrayList called `nums` containing: `[5, 10, 15, 20]` Perform these operations:

1. nums.add(2, 12)
2. nums.remove(Integer.valueOf(10))
3. nums.add(0, 3)
4. nums.remove(nums.size()-1)
5. nums.add(nums.get(1))

Show the final contents of the ArrayList:

Final answer: [______, ______, ______, ______, ______]

Question 3

Start with an ArrayList called `colors` containing: `["red", "blue", "green"]` Perform these operations:

1. colors.add("yellow")
2. colors.set(1, "purple")
3. colors.remove(2)
4. colors.add(1, "orange")
5. colors.remove("red")
6. colors.add(colors.get(0))

Show the final contents of the ArrayList:

Final answer: [______, ______, ______, ______]

Question 4

Start with an ArrayList called `nums` containing: `[2, 4, 6, 8, 10, 12, 14]` Perform these operations:

1. nums.add(3)
2. For loop that runs forward through the list:

   for(int i = 0; i < nums.size(); i++) {
    if(nums.get(i) % 4 == 0) {
        nums.remove(i);
    }
   }
   

3. nums.add(0, 1)
4. For loop that doubles each number:

   for(int i = 0; i < nums.size(); i++) {
    nums.set(i, nums.get(i) * 2);
   }
   

Show the final contents of the ArrayList:

Final answer: [______, ______, ______, ______, ______, ______]