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How to Solve Number of Senior Citizens Problem
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Easy#2678
LeetCode ProblemNumber of Senior Citizens
You are given a 0-indexed array of strings details. Each element of details provides information about a given passenger compressed into a string of length 15. The system is such that: Return the number of passengers who are strictly more than 60 years old.
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Problem Breakdown
Understanding the Number of Senior Citizens Problem
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Problem Statement
You are given a 0-indexed array of strings details. Each element of details provides information about a given passenger compressed into a string of length 15. The system is such that: Return the number of passengers who are strictly more than 60 years old.
Examples
# Example 1
Input
details = ["7868190130M7522","5303914400F9211","9273338290F4010"]
Output
2
# Example 2
Input
details = ["1313579440F2036","2921522980M5644"]
Output
0
Constraints
1 <= details.length <= 100
details[i].length == 15
details[i] consists of digits from '0' to '9'.
details[i][10] is either 'M' or 'F' or 'O'.
The phone numbers and seat numbers of the passengers are distinct.
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Solve Number of Senior Citizens — You are given a 0-indexed array of strings details. Each element of details prov...
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def solve(input):
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Frequently Asked Questions
Common questions about solving Number of Senior Citizens and using PhantomCodeAI during coding interviews.
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PhantomCodeAI reads the problem from a screenshot or listens to it via audio, then generates a complete solution with a step-by-step approach and time/space complexity, so you can focus on explaining your reasoning rather than getting stuck on implementation.
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