Path Sum Root to Leaf in Binary Tree in DSA Go - Interactive Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check if the current node is a leaf node.

DSA Go

if root.Left == nil && root.[1] == nil {

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AChild

BRight

CParent

DNext

Attempts:

3 left

💡 Hint

Common Mistakes

Checking for Parent or Next instead of Right child.

Using incorrect field names.

A leaf node has no left or right children, so both must be nil.

2fill in blank

medium

Complete the code to subtract the current node's value from the sum.

DSA Go

return hasPathSum(root.Left, sum - root.[1]) || hasPathSum(root.Right, sum - root.Val)

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ANum

BValue

CData

DVal

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Value' or 'Data' which are not valid field names.

Using 'Num' which is not defined.

The node's value is stored in the field 'Val' in Go binary tree nodes.

3fill in blank

hard

Fix the error in the base case to correctly return false when the node is nil.

DSA Go

if root == [1] {
    return false
}

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Anil

B0

Cnull

DNone

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'null' or 'None' instead of 'nil'.

Using 0 which is not a pointer.

In Go, the nil keyword is used to check if a pointer is empty or not pointing to any node.

4fill in blank

hard

Fill both blanks to correctly check if the current node is a leaf and if the sum matches the node's value.

DSA Go

if root.Left == nil && root.Right == nil {
    return sum == root.[1] 
} else {
    return hasPathSum(root.[2], sum - root.Val) || hasPathSum(root.Right, sum - root.Val)
}

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AVal

BLeft

CRight

DData

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Data' instead of 'Val'.

Using 'Right' for the first recursive call instead of 'Left'.

The node's value is in 'Val'. For the recursive call, we check the left child first using 'Left'.

5fill in blank

hard

Fill all three blanks to complete the recursive calls checking both children with updated sums.

DSA Go

return hasPathSum(root.[1], sum - root.[2]) || hasPathSum(root.[3], sum - root.Val)

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

ALeft

BVal

CRight

DData

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'Data' instead of 'Val'.

Mixing up child pointers in recursive calls.

We recurse on the left child with sum minus root.Val, and on the right child similarly.