Valid palindrome "neetcode" #58

Problem

Check if "neetcode" is palindrome (alphanumeric only); print True or False.

Examples

Sample

Output

False

Hints

Skip non-alphanumeric

Your solution

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Solution

using System;
using System.Collections.Generic;
using System.Linq;

class Program
{
    static void Main()
    {
        string s = "neetcode";
        int l = 0, r = s.Length - 1;
        while (l < r) {
            while (l < r && !char.IsLetterOrDigit(s[l])) l++;
            while (l < r && !char.IsLetterOrDigit(s[r])) r--;
            if (char.ToLower(s[l]) != char.ToLower(s[r])) { Console.WriteLine("False"); return; }
            l++; r--;
        }
        Console.WriteLine("True");
    }
}

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Explanation

Two-pointer palindrome check.

Problem

Examples

Your solution

Solution

Explanation

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