36 lines
901 B
C#
36 lines
901 B
C#
using System;
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using System.Collections.Generic;
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using System.Linq;
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using System.Text;
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namespace First_week
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{
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public static class CollectionUtils
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{
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public static bool IsNullOrEmpty<T>(this IEnumerable<T> collection)
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{
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return collection == null || !collection.Any();
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}
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public static List<T> ToSafeList<T>(this IEnumerable<T> collection)
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{
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return collection?.ToList() ?? new List<T>();
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}
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public static void Shuffle<T>(this IList<T> list)
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{
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if (list == null)
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return;
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Random rng = new Random();
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int n = list.Count;
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while (n > 1)
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{
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n--;
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int k = rng.Next(n + 1);
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T value = list[k];
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list[k] = list[n];
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list[n] = value;
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}
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}
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}
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} |