Two Pointer Quiz

What is the two-pointer technique commonly used for?

• Sorting

• Searching and traversal

• Recursion

• Memoization

In the two-pointer approach, the pointers move in which directions?

• Both start to end

• One from start, one from end

• Both from end

• Random
  

Which type of problems is the two-pointer technique most effective for?

• Binary Trees

• Linked Lists

• Sorted Arrays

• Graphs

Which of the following can be solved using the two-pointer technique?

• 2Sum in sorted array

• Palindrome check

• Merge two sorted arrays

• All of the above

Which condition should be used to move the left pointer in a sorted array for 2Sum if current sum is less than target?

• left--

• left++

• right--

• right++

What is the time complexity of the two-pointer approach (on a sorted array)?

• O(n²)

• O(log n)

• O(n log n)

• O(n)

Which two-pointer pattern best suits finding a subarray with a given sum in a positive integer array?

• Sliding window

• Merge sort

• Binary search

• DFS

In merging two sorted arrays, what does the two-pointer approach help avoid?

• Extra memory

• Nested loops

• Re-sorting

• All of the above

What are typical use cases for the two-pointer technique?

• Comparing elements from both ends of an array

• Iterating through a hash map

• Sliding window problems

• Partitioning arrays (like in quicksort)

Which conditions should you consider while implementing a two-pointer solution for arr[i] + arr[j] == target on a sorted array?

• Increment i if sum < target

• Decrement j if sum > target

• Increment both i and j if sum < target

• Stop when i >= j