Slice length and capacity in Go - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a slice with length 3.

Go

s := make([]int, [1])
fmt.Println(len(s))

Drag options to blanks, or click blank then click option'

A5

B0

C3

D10

Attempts:

3 left

💡 Hint

Common Mistakes

Using capacity instead of length in the make function.

Confusing length with capacity.

The make function creates a slice with the specified length. Here, length 3 means the slice has 3 elements.

2fill in blank

medium

Complete the code to create a slice with length 3 and capacity 5.

Go

s := make([]int, 3, [1])
fmt.Println(cap(s))

Drag options to blanks, or click blank then click option'

A0

B10

C3

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Setting capacity smaller than length causes a compile error.

Confusing length and capacity positions in make.

The third argument in make sets the capacity of the slice. Here, capacity 5 means the slice can grow up to 5 elements without reallocating.

3fill in blank

hard

Fix the error in the code to print the length of the slice.

Go

s := []int{1, 2, 3}
fmt.Println([1](s))

Drag options to blanks, or click blank then click option'

Acap

Blen

Csize

Dlength

Attempts:

3 left

💡 Hint

Common Mistakes

Using cap instead of len to get length.

Using non-existent functions like size or length.

The built-in function len returns the length of a slice in Go.

4fill in blank

hard

Fill both blanks to create a slice with length 2 and capacity 4, then print length and capacity.

Go

s := make([]int, [1], [2])
fmt.Println(len(s), cap(s))

Drag options to blanks, or click blank then click option'

A2

B3

C4

D5

Attempts:

3 left

💡 Hint

Common Mistakes

Swapping length and capacity values.

Setting capacity smaller than length.

The first blank is the length (2), and the second blank is the capacity (4). The make function uses these to create the slice.

5fill in blank

hard

Fill the blanks to create a slice from an array, then print its length and capacity.

Go

arr := [5]int{1, 2, 3, 4, 5}
s := arr[[1]:[2]]
fmt.Println(len(s), cap(s))

Drag options to blanks, or click blank then click option'

A1

B2

C5

D3

Attempts:

3 left

💡 Hint

Common Mistakes

Confusing slice length with capacity.

Using wrong indices for slicing.

The slice s starts at index 1 and ends before index 3, so length is 2. Capacity is from start index 1 to end of array index 5, so capacity is 4.