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How to Solve Friends Of Appropriate Ages Problem
Master the Friends Of Appropriate Ages LeetCode problem with undetectable real-time assistance. Get instant solutions and explanations during your coding interviews.
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Start Free for WindowsMedium#825
LeetCode ProblemFriends Of Appropriate Ages
There are n persons on a social media website. You are given an integer array ages where ages[i] is the age of the ith person. A Person x will not send a friend request to a person y (x != y) if any of the following conditions is true: Otherwise, x will send a friend request to y. Note that if x sends a request to y, y will not necessarily send a request to x. Also, a person will not send a friend request to themself. Return the total number of friend requests made.
ArrayTwo PointersBinary SearchSorting
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Problem Breakdown
Understanding the Friends Of Appropriate Ages Problem
Let's break down this LeetCode problem and understand what makes it challenging in interview settings.
Problem Statement
There are n persons on a social media website. You are given an integer array ages where ages[i] is the age of the ith person. A Person x will not send a friend request to a person y (x != y) if any of the following conditions is true: Otherwise, x will send a friend request to y. Note that if x sends a request to y, y will not necessarily send a request to x. Also, a person will not send a friend request to themself. Return the total number of friend requests made.
MediumProblem #825
LeetCodeFriends Of Appropriate Ages
Related Topics
ArrayTwo PointersBinary SearchSorting
How Phantom Code Helps
Get real-time assistance for Friends Of Appropriate Ages problems during coding interviews. Phantom Code provides instant solutions and explanations.
Examples
# Example 1
Input
ages = [16,16]
Output
2
# Example 2
Input
ages = [16,17,18]
Output
2
# Example 3
Input
ages = [20,30,100,110,120]
Output
3
Constraints
n == ages.length
1 <= n <= 2 * 104
1 <= ages[i] <= 120
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Solve Friends Of Appropriate Ages — There are n persons on a social media website. You are given an integer array ag...
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 Friends Of Appropriate Ages and using Phantom Code during coding interviews.
How does Phantom Code help me solve coding problems like Friends Of Appropriate Ages 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 Friends Of Appropriate Ages?
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 Friends Of Appropriate Ages?
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 Friends Of Appropriate Ages 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 Friends Of Appropriate Ages 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 Friends Of Appropriate Ages 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 Friends Of Appropriate Ages 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 Friends Of Appropriate Ages 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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