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@tigrouind
Created September 25, 2019 12:46
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using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
namespace Test
{
class Program
{
static Random rand = new Random();
public static int[] GetArray()
{
List<int> res = new List<int>();
for(int i = 0 ; i < rand.Next(1, 4) ; i++)
{
res.Add(rand.Next(1, 100));
}
return res.ToArray();
}
public static void Main()
{
var items = Enumerable.Range(0, 5000)
.Select(x => new { Name = x.ToString(), Values = GetArray() })
.ToList();
Stopwatch sw = Stopwatch.StartNew();
sw.Start();
var tuples = items
.SelectMany(x => x.Values, (x, y) => new { x.Name, Value = y })
.ToList();
var result = tuples.Join(tuples,
x => x.Value,
x => x.Value,
(x, y) => new { NameA = x.Name, NameB = y.Name })
.Where(x => x.NameA != x.NameB)
.Distinct()
.GroupBy(x => x.NameA, x => x.NameB, (x, y) => new { x, y = y.ToList() })
.ToList();
sw.Stop();
Console.WriteLine(sw.Elapsed);
sw = Stopwatch.StartNew();
var hashed = items
.Select(i => new { i.Name, Values = i.Values.ToHashSet() })
.ToList();
var overlaps = hashed.Select(h1 => new
{
h1.Name,
Overlaps = hashed
.Where(h2 => h2.Name != h1.Name && h2.Values.Overlaps(h1.Values))
.Select(h => h.Name)
.ToList()
}).ToList();
Console.WriteLine(sw.Elapsed);
Console.ReadLine();
}
}
}
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