Two Pointers Questions at Accenture: What to Expect

Two Pointers is a high-frequency pattern at Accenture, appearing in 26 of their 144 coding questions. This 18% representation means you have a roughly 1 in 5 chance of encountering it during your technical screen. Mastering it is non-negotiable for efficient problem-solving in their time-constrained interviews. The pattern is favored because it elegantly solves problems on sorted arrays or sequences, demonstrating your ability to optimize from a brute-force O(n²) solution to a linear O(n) one—a key skill Accenture assesses for writing performant, scalable code.

What to Expect — Types of Problems

Accenture's Two Pointers problems typically fall into three categories. First, pair searching in a sorted array, like finding two numbers that sum to a target. Second, in-place array manipulation, such as removing duplicates or segregating elements (e.g., moving all zeros to the end). Third, sequence comparison, often involving strings, like checking for a palindrome or finding a minimum window. These questions test your ability to recognize when a sorted input or a directional traversal can simplify the logic. Expect the difficulty to range from easy to medium, focusing on clean implementation over complex algorithm design.

How to Prepare — Study Tips with One Code Example

Focus on the core mechanic: initializing two indices (often at the start and end, or both at the start) and moving them conditionally to reduce the search space. Practice drawing the pointer movements on a whiteboard. Always start by clarifying if the input is sorted; if not, sorting it might be the first step. For preparation, solve at least 10-15 problems, ensuring you cover all three problem types.

A fundamental pattern is the opposite-directional two-pointer search. Consider finding a pair in a sorted array that sums to a target.

def two_sum_sorted(numbers, target):
    left, right = 0, len(numbers) - 1
    while left < right:
        current_sum = numbers[left] + numbers[right]
        if current_sum == target:
            return [left, right]  # or return [left + 1, right + 1] for 1-indexed
        elif current_sum < target:
            left += 1  # Need a larger sum
        else:
            right -= 1  # Need a smaller sum
    return []  # No solution

Recommended Practice Order

Build competency progressively. Start with basic pair search (Two Sum II, Valid Palindrome). Move to in-place array operations (Remove Duplicates, Move Zeroes). Then tackle sliding window problems (Minimum Window Substring—a harder variant). Finally, practice Accenture's tagged company questions to familiarize yourself with their specific phrasing and constraints. Time yourself to simulate interview pressure.

Practice Two Pointers at Accenture