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ArrayList index out of bounds
int size = 2:
ArrayList<Integer[]> nums = new ArrayList<Integer[]>(size);
Integer[] value1 = {1,2,3};
Integer[] value2 = {1,2};
nums.add(1,value1); // java.lang.IndexOutOfBoundsException
nums.add(0,value2);

int size = 2:
ArrayList<Integer[]> nums = new ArrayList<Integer[]>(size);
Integer[] value1 = {1,2,3};
Integer[] value2 = {1,2};
nums.add(0, null);
nums.add(1,value1);
nums.set(0,value2);

nums.add(value2);
nums.add(value1);

nums.add(0, value1);
nums.add(0, value2);

ArrayList<Integer[]> nums = new ArrayList<Integer[]>(size);

int size = 2:
ArrayList<Integer[]> nums = new ArrayList<Integer[]>(size);
Integer[] value1 = {1,2,3};
Integer[] value2 = {1,2};
System.out.println(nums.size());
nums.add(value2);
System.out.println(nums.size());
nums.add(value1);
System.out.println(nums.size());

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