Longest Palindromic Substring in Beef

Published on 11 February 2024 (Updated: 11 February 2024)

Welcome to the Longest Palindromic Substring in Beef page! Here, you'll find the source code for this program as well as a description of how the program works.

Current Solution

``````using System;

namespace LongestPalindromicSubstring;

class Program
{
public static void Usage()
{
Console.WriteLine("Usage: please provide a string that contains at least one palindrome");
Environment.Exit(0);
}

// Find longest palindromic string using matching array
// Source: https://www.geeksforgeeks.org/longest-palindromic-substring-using-dynamic-programming/
public static void LongestPalindromicSubstring(StringView str, String longest)
{
// Convert string to lowercase
String strLower = scope .(str) .. ToLower();

// Initialize character match matrix to indicate length 1 strings match
int n = str.Length;
bool [,] matches = scope .[n, n];
for (int i < n)
{
matches[i, i] = true;
}

// Find all length 2 matches
int start = 0;
int maxLen = 1;
for (int i < (n - 1))
{
if (strLower[i] == strLower[i + 1])
{
matches[i, i + 1] = true;
start = i;
maxLen = 2;
}
}

// Find all length 3 or longer matches
for (int len in 3...n)
{
// Loop through each starting character
int j = len - 1;
for (int i in 0...(n - len))
{
// If match for one character in from start and end characters
// and start and end characters match, set match for start and
// end characters, and update max length
if (matches[i + 1, j - 1] && strLower[i] == strLower[j])
{
matches[i, j] = true;
if (len > maxLen)
{
start = i;
maxLen = len;
}
}

j++;
}
}

longest.Clear();
longest.Append(str[start..<(start + maxLen)]);
}

public static int Main(String[] args)
{
if (args.Count < 1 || args[0].Length < 1)
{
Usage();
}

String result = scope .();
LongestPalindromicSubstring(args[0], result);
if (result.Length < 2)
{
Usage();
}

Console.WriteLine(result);

return 0;
}
}

``````

Longest Palindromic Substring in Beef was written by:

• rzuckerm

If you see anything you'd like to change or update, please consider contributing.

How to Implement the Solution

No 'How to Implement the Solution' section available. Please consider contributing.

How to Run the Solution

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