54 lines
1.3 KiB
C#
54 lines
1.3 KiB
C#
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using System;
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using System.Collections.Generic;
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using System.Linq;
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public static class EnumerableSelectionExtensions
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{
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public static T MaxBy<T, U>(this IEnumerable<T> items, Func<T, U> selector)
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{
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if (!items.Any())
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{
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throw new InvalidOperationException("Empty input sequence");
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}
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var comparer = Comparer<U>.Default;
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var maxItem = items.First();
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var maxValue = selector(maxItem);
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foreach (var item in items.Skip(1))
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{
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var value = selector(item);
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if (comparer.Compare(value, maxValue) > 0)
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{
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maxValue = value;
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maxItem = item;
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}
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}
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return maxItem;
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}
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public static T MinBy<T, U>(this IEnumerable<T> items, Func<T, U> selector)
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{
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if (!items.Any())
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{
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throw new InvalidOperationException("Empty input sequence");
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}
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var comparer = Comparer<U>.Default;
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var minItem = items.First();
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var minValue = selector(minItem);
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foreach (var item in items.Skip(1))
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{
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var value = selector(item);
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if (comparer.Compare(value, minValue) < 0)
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{
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minValue = value;
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minItem = item;
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}
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}
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return minItem;
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}
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}
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