DDSA Solutions

2678. Number of Senior Citizens

EasyView on LeetCode
ArrayStringSimulation
Time: O(n)
Space: O(1)

Problem Overview

Number of Senior Citizens (Easy) asks you to solve a structured algorithmic task. This is a common Array / String pattern in coding interviews. Parse age from chars at index 11-12 of each detail string; count those > 60.

A full step-by-step explanation is being added. See the study guide for pattern-based practice.

Approach

Parse age from chars at index 11-12 of each detail string; count those > 60.

Related patterns: Array, String, Simulation

2678.cs
C#
// Approach: Parse age from chars at index 11-12 of each detail string; count those > 60.
// Time: O(n) Space: O(1)

public class Solution
{
    public int CountSeniors(string[] details)
    {
        // foreach(string d in details)
        //     Console.WriteLine(d.Substring(11, 2));

        return details.Where(x => Int32.Parse(x.Substring(11, 2)) > 60).Count();
    }
}
Was this solution helpful?

Related Problems