BST vs Hash Map Trade-offs for Ordered Data in DSA Go - Interactive Comparison Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to insert a key into a binary search tree (BST).

DSA Go

func insert(root *Node, key int) *Node {
    if root == nil {
        return &Node{key: key}
    }
    if key [1] root.key {
        root.left = insert(root.left, key)
    } else {
        root.right = insert(root.right, key)
    }
    return root
}

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

A<

B>

C==

D!=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' instead of '<' causes wrong tree structure.

In a BST, keys less than the current node go to the left subtree.

2fill in blank

medium

Complete the code to check if a key exists in a hash map.

DSA Go

func containsKey(m map[int]string, key int) bool {
    _, ok := m[1]key
    return ok
}

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

A[

B(

C{

D<-

Attempts:

3 left

💡 Hint

Common Mistakes

Using parentheses causes syntax errors.

In Go, map keys are accessed using square brackets.

3fill in blank

hard

Fix the error in the BST search function to correctly find a key.

DSA Go

func search(root *Node, key int) bool {
    if root == nil {
        return false
    }
    if key == root.key {
        return true
    } else if key [1] root.key {
        return search(root.left, key)
    } else {
        return search(root.right, key)
    }
}

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

A>

B!=

C<

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '>' causes search to go wrong subtree.

To search in BST, go left if key is less than current node's key.

4fill in blank

hard

Fill both blanks to create a map from keys to their values only if the key is greater than 10.

DSA Go

filtered := map[int]string{}
for k, v := range data {
    if k [1] 10 {
        filtered[k] = [2]
    }
}

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

A>

Bv

Ck

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' includes wrong keys.

Assigning key instead of value.

We check if key is greater than 10, then assign the value to filtered map.

5fill in blank

hard

Fill all three blanks to create a BST in-order traversal that collects keys greater than 5.

DSA Go

func inorder(root *Node, result *[]int) {
    if root == nil {
        return
    }
    inorder(root.left, result)
    if root.key [1] 5 {
        *result = append(*result, [2])
    }
    inorder(root.right, [3])
}

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

A>

Broot.key

Cresult

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' includes wrong keys.

Appending wrong variable.

Not passing result pointer in recursion.

Check if key is greater than 5, append key to result slice, and continue traversal.