Slice and array relationship in Go - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is a slice in Go?

A slice in Go is a flexible, dynamic view into the elements of an array. It does not store data itself but references an underlying array.

beginner

How does a slice relate to its underlying array?

A slice points to a segment of an array. Changes to the slice elements affect the underlying array and vice versa.

intermediate

What happens when you append to a slice that has no extra capacity?

Go creates a new underlying array with more capacity, copies the old elements, and appends the new ones. The slice then points to this new array.

beginner

How can you create a slice from an array?

You can create a slice by specifying a range of indices on an array, like: slice := array[start:end].

beginner

Does modifying a slice affect the original array?

Yes, because the slice references the original array's elements, modifying the slice changes the array's data.

What does a Go slice store internally?

A Only the length of the array

B A copy of the array elements

C A pointer to an array, length, and capacity

D The entire array data

A slice stores a pointer to the underlying array, its length, and its capacity.

If you change an element in a slice, what happens to the underlying array?

A The array element changes too

B The array remains unchanged

C The array is copied and changed separately

D The slice breaks the link to the array

Slices reference the array, so changes to the slice affect the array.

What happens when you append to a slice that has enough capacity?

A The program crashes

B A new array is created

C The slice length stays the same

D The element is added to the existing array

If capacity allows, append adds elements to the existing array without creating a new one.

How do you create a slice from an array named 'arr' from index 2 to 5?

A slice := arr[3:5]

B slice := arr[2:5]

C slice := arr[2:6]

D slice := arr[2..5]

The slice syntax includes the start index and excludes the end index, so arr[2:5] includes indices 2,3,4.

Which of these is true about slices in Go?

A Slices can grow beyond the size of the underlying array

B Slices always copy the array data

C Slices cannot be created from arrays

D Slices have fixed length and capacity

Slices can grow by allocating a new underlying array when capacity is exceeded.

Explain how a slice and its underlying array are connected in Go.

Think about how slices are views into arrays.

Describe what happens internally when you append an element to a slice that has no remaining capacity.

Consider slice capacity and memory allocation.