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

namespace FuzzyString
{
	public static partial class ComparisonMetrics
	{
		public static double RatcliffObershelpSimilarity(this string source, string target)
		{
			return (2 * Convert.ToDouble(source.Intersect(target).Count())) / (Convert.ToDouble(source.Length + target.Length));
		}
	}
}