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How to Solve Best Time to Buy and Sell Stock Problem
Master the Best Time to Buy and Sell Stock LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
Phantom Code generates complete solutions and debugging hints that you can use while explaining your approach, so you stay calm and in control.
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Start Free for WindowsEasy#121
LeetCode ProblemBest Time to Buy and Sell Stock
You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock. Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0.
ArrayDynamic Programming
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Problem Breakdown
Understanding the Best Time to Buy and Sell Stock Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
You are given an array prices where prices[i] is the price of a given stock on the ith day. You want to maximize your profit by choosing a single day to buy one stock and choosing a different day in the future to sell that stock. Return the maximum profit you can achieve from this transaction. If you cannot achieve any profit, return 0.
EasyProblem #121
LeetCodeBest Time to Buy and Sell Stock
Related Topics
ArrayDynamic Programming
How Phantom Code Helps
Get real-time assistance for Best Time to Buy and Sell Stock problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
prices = [7,1,5,3,6,4]
Output
5
# Example 2
Input
prices = [7,6,4,3,1]
Output
0
Constraints
1 <= prices.length <= 105
0 <= prices[i] <= 104
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Solve Best Time to Buy and Sell Stock — You are given an array prices where prices[i] is the price of a given stock on t...
Here's the optimal approach using Array:
def solve(input):
# Optimal O(n) solution
return result
Time: O(n) | Space: O(n)
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Frequently Asked Questions
Common questions about solving Best Time to Buy and Sell Stock and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Best Time to Buy and Sell Stock during interviews?
Phantom Code generates complete solutions instantly with proper complexity analysis, letting you focus on explaining your approach and demonstrating problem-solving skills rather than getting stuck on implementation details during high-pressure situations.
What if the interviewer asks follow-up questions or modifications to problems like Best Time to Buy and Sell Stock?
Phantom Code adapts in real-time. Screenshot the modified problem or use audio mode to capture the interviewer's follow-up, and get an updated solution within seconds — including edge cases and optimizations.
Can Phantom Code help me communicate my solution for problems like Best Time to Buy and Sell Stock?
Yes. Phantom Code provides step-by-step approach explanations with 3 progressive thoughts, so you can walk through your solution naturally. It also provides time and space complexity analysis to discuss trade-offs.
How does Phantom Code assist with different programming languages for Best Time to Buy and Sell Stock type problems?
Phantom Code supports 11 programming languages including Python, Java, C++, JavaScript, TypeScript, Go, Rust, Ruby, Swift, Kotlin, and C#. Set your preferred language and get idiomatic solutions.
What coding mistakes does Phantom Code help me avoid during Best Time to Buy and Sell Stock interviews?
Phantom Code catches common mistakes like off-by-one errors, missing edge cases, incorrect base conditions, and suboptimal approaches. It provides clean, well-structured code that handles all edge cases.
Is Phantom Code detectable when solving problems like Best Time to Buy and Sell Stock during live interviews?
No. Phantom Code runs as an invisible desktop overlay that doesn't appear in screen shares, recordings, or proctoring software. It works with Zoom, HackerRank, CodeSignal, CoderPad, and all major platforms.
How does Phantom Code help when I'm struggling with Best Time to Buy and Sell Stock style questions under pressure?
The AI provides structured guidance: first the approach (what algorithm/data structure to use and why), then the implementation with clean code, and finally complexity analysis. This helps you think clearly even under pressure.
Does Phantom Code work for the coding platforms used in Best Time to Buy and Sell Stock interviews?
Yes. Phantom Code works with all major coding platforms including LeetCode, HackerRank, CodeSignal, CoderPad, HackerEarth, and any browser-based coding environment.
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