Deep Copy and Shallow Copy

Shallow Copy

Copies as little as possible.
A new structure created by a shallow copy has the same structure as the old one,
and they share the memory address of elements.

For example, in Java:

int[] arr1 = {1, 2, 3};
int[] arr2 = arr1;

arr2 is a shallow copy of arr1.

• If one of the structures modifies an element, the other will also be affected.

Deep Copy

Copies everything.
A new structure created by a deep copy not only has the same structure as the old one,
but also copies all elements of the old structure to the new memory address.

int[] arr1 = {1, 2, 3};
int[] arr2 = new int[arr1.length];

for (int i = 0; i < arr1.length; ++i) {
	arr2[i] = arr1[i];
}

arr2 is a deep copy of arr1.

• It occupies more memory space.