GeneralStringAlgorithms.cs

using System;

namespace Algorithms.Strings;

/// <summary>
///     Implements simple algorithms on strings.
/// </summary>
public static class GeneralStringAlgorithms
{
    /// <summary>
    ///     Finds character that creates longest consecutive substring with single character.
    /// </summary>
    /// <param name="input">String to find in.</param>
    /// <returns>Tuple containing char and number of times it appeared in a row.</returns>
    public static Tuple<char, int> FindLongestConsecutiveCharacters(string input)
    {
        var maxChar = input[0];

        var max = 1;
        var current = 1;

        for (var i = 1; i < input.Length; i++)
        {
            if (input[i] == input[i - 1])
            {
                current++;
                if (current > max)
                {
                    max = current;
                    maxChar = input[i];
                }
            }
            else
            {
                current = 1;
            }
        }

        return new Tuple<char, int>(maxChar, max);
    }
}