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This is a medium difficulty Coding & Algorithms question, commonly asked during Take-home Project rounds at Amazon.

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This question is commonly asked for Software Engineer candidates at Amazon during technical interviews.

Build the Largest Available Sequence

Last updated: May 7, 2026

Quick Overview

This question evaluates algorithmic problem-solving skills in state simulation, constrained selection, and lexicographic sequence maximization, measuring the ability to reason about evolving availability when constructing sequences.

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Build the Largest Available Sequence

Amazon

Apr 14, 2026, 12:00 AM

mediumSoftware EngineerTake-home ProjectCoding & Algorithms

Practice Read

You are given an integer array values, a binary string state of the same length, and an integer m such that 0 <= m <= values.length.

Build a sequence s of length m using exactly m operations. You may assume it is always possible to complete all m picks.

In each operation:

Choose any index i such that state[i] = '1' .
Append values[i] to s .
Mark that index as unavailable by setting state[i] = '0' .
Then perform one simultaneous availability update on this new state: for every index j > 0 , if state[j - 1] = '1' and state[j] = '0' , flip state[j] to 1 .

Return the lexicographically largest possible sequence s. For integer sequences, lexicographic order compares elements from left to right.

Example:

values = [10, 5, 7, 6]
state = "0101"
m = 2

One optimal answer is [6, 7].

Write a function to compute the lexicographically largest sequence.