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using System;
using System.Collections;
using System.Collections.Generic;
using AlgorithmCollection;
namespace AlgorithmCollection.Searching
{
public static class SearchingHelper
{
// 二分搜索，返回索引号
// O(logn)
public static int BinarySearch<T>(T[] dataList, T value) where T : IComparable, IEquatable<T>
{
int n = dataList.Length;
int left = 0;
int right = n - 1;
while(left <= right)
{
int middle = (right + left) / 2;
T midValue = dataList[middle];
if (value.Equals(midValue))
return middle;
if (value.CompareTo(midValue) > 0)
left = middle + 1;
if (value.CompareTo(midValue) < 0)
right = middle - 1;
}
return -1; // 没找到
}
}
}
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