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How to Solve Alert Using Same Key-Card Three or More Times in a One Hour Period Problem
Master the Alert Using Same Key-Card Three or More Times in a One Hour Period LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsMedium#1604
LeetCode ProblemAlert Using Same Key-Card Three or More Times in a One Hour Period
LeetCode company workers use key-cards to unlock office doors. Each time a worker uses their key-card, the security system saves the worker's name and the time when it was used. The system emits an alert if any worker uses the key-card three or more times in a one-hour period. You are given a list of strings keyName and keyTime where [keyName[i], keyTime[i]] corresponds to a person's name and the time when their key-card was used in a single day. Access times are given in the 24-hour time format "HH:MM", such as "23:51" and "09:49". Return a list of unique worker names who received an alert for frequent keycard use. Sort the names in ascending order alphabetically. Notice that "10:00" - "11:00" is considered to be within a one-hour period, while "22:51" - "23:52" is not considered to be within a one-hour period.
ArrayHash TableStringSorting
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Problem Breakdown
Understanding the Alert Using Same Key-Card Three or More Times in a One Hour Period Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
LeetCode company workers use key-cards to unlock office doors. Each time a worker uses their key-card, the security system saves the worker's name and the time when it was used. The system emits an alert if any worker uses the key-card three or more times in a one-hour period. You are given a list of strings keyName and keyTime where [keyName[i], keyTime[i]] corresponds to a person's name and the time when their key-card was used in a single day. Access times are given in the 24-hour time format "HH:MM", such as "23:51" and "09:49". Return a list of unique worker names who received an alert for frequent keycard use. Sort the names in ascending order alphabetically. Notice that "10:00" - "11:00" is considered to be within a one-hour period, while "22:51" - "23:52" is not considered to be within a one-hour period.
MediumProblem #1604
LeetCodeAlert Using Same Key-Card Three or More Times in a One Hour Period
Related Topics
ArrayHash TableStringSorting
How Phantom Code Helps
Get real-time assistance for Alert Using Same Key-Card Three or More Times in a One Hour Period problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
keyName = ["daniel","daniel","daniel","luis","luis","luis","luis"], keyTime = ["10:00","10:40","11:00","09:00","11:00","13:00","15:00"]
Output
["daniel"]
# Example 2
Input
keyName = ["alice","alice","alice","bob","bob","bob","bob"], keyTime = ["12:01","12:00","18:00","21:00","21:20","21:30","23:00"]
Output
["bob"]
Constraints
1 <= keyName.length, keyTime.length <= 105
keyName.length == keyTime.length
keyTime[i] is in the format "HH:MM".
[keyName[i], keyTime[i]] is unique.
1 <= keyName[i].length <= 10
keyName[i] contains only lowercase English letters.
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Solve Alert Using Same Key-Card Three or More Times in a One Hour Period — LeetCode company workers use key-cards to unlock office doors. Each time a worke...
Here's the optimal approach using Array:
def solve(input):
# Optimal O(n) solution
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Time: O(n) | Space: O(n)
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Frequently Asked Questions
Common questions about solving Alert Using Same Key-Card Three or More Times in a One Hour Period and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Alert Using Same Key-Card Three or More Times in a One Hour Period 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 Alert Using Same Key-Card Three or More Times in a One Hour Period?
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 Alert Using Same Key-Card Three or More Times in a One Hour Period?
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 Alert Using Same Key-Card Three or More Times in a One Hour Period 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 Alert Using Same Key-Card Three or More Times in a One Hour Period 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 Alert Using Same Key-Card Three or More Times in a One Hour Period 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 Alert Using Same Key-Card Three or More Times in a One Hour Period 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 Alert Using Same Key-Card Three or More Times in a One Hour Period 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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