从未排序的数组中删除重复的最大值和最小值

Question

我目前有一些包含以下值的数组

var array = new[] { 4, 7, 9, 3, 8, 6, 4, 3, 3, 9};

我需要删除最小值和最大值的重复项，因此在这种情况下，最终产品将是

var array = new[] { 4, 7, 9, 3, 8, 6, 4};

Answer 1

----------已编辑-------------- ----

////Correct        
        Int32[] arr = { 4, 7, 9, 3, 8, 6, 4, 3, 3, 9 };
        List<Int32> newArr = new List<Int32>();
        Int32 max = arr.Max();
        Int32 min = arr.Min();
        Boolean removeMax = false;
        Boolean removeMin = false;

        foreach (var each in arr)
        {                
            if (each == min || each == max)
            {
                if (!removeMax || !removeMin)
                {
                    if (each == min)
                    {
                        newArr.Add(each);
                        removeMin = true;
                    }

                    if (each == max)
                    {
                        newArr.Add(each);
                        removeMax = true;
                    }                        
                }
            }
            else
            {
                newArr.Add(each);
            }               
        }
        var arrAfter = newArr.ToArray();           

Answer 2

这将只需要迭代array 两次。

 var max = int.MinValue;
 var min = int.MaxValue;
 var array = new [] { 4, 7, 9, 3, 8, 6, 4, 3, 3, 9 };
 // Get min and max values. With just one iteration.
 foreach (var element in array)
     {
     if (element < min)
         {
         min = element;
         }
     if (max < element)
         {
         max = element;
         }
     }

 var minCount = 0;
 var maxCount = 0;
 var list = array.ToList ();
 // Search for duplicates with second iteration.
 for (int i = 0; i < list.Count; ++i)
     {
     if (list[i] == min)
         {
         if (minCount++ != 0)
             {
             list.RemoveAt (i--);
             }
         continue;
         }
     if (list[i] == max)
         {
         if (maxCount++ != 0)
             {
             list.RemoveAt (i--);
             }
         }
     }
 array = list.ToArray ();

Answer 3

如果性能不是问题那么这样的事情会起作用

var min = arr.Min();
var max = arr.Max();

bool foundMin = false, foundMax = false;
var result = arr
               .Where(a=>!((a==min && foundMin) || (a==max &&foundMax)))
               .Select(a=>{ 
                    if(a==min) 
                    {
                       foundMin = true;
                    }
                    else if(a==max) 
                    {
                      foundMax = true;
                    }

                    return a;
            }).ToArray();

我想不出用少于两次的方法来做到这一点，所以我能看到的唯一改进是创建一个循环来同时找到最小值和最大值

int min,max;
for(int i=0;i<arr.length;i++)
{
    if(i==0) min = max = arr[i];
    else if(arr[i]<min) 
    {
        min = arr[i];
    } 
    else if (arr[i]>max)
    {
        max = arr[i];
    }
}

但如果您不关心性能，只需使用内置的 linq 方法，因为它的代码较少，但前提是性能不是问题

作为常规循环

//assuming calculated min & max with loop or .Min & .Max linq extensions
var newLs = new List<int>();
int[] result;
bool foundMin = false, foundMax = false;
foreach(var val in arr)
{
    if(val == min)
    {
        if(foundMin) continue;
        foundMin = true;
    }
    if(val == max)
    {
       if(foundMax) continue;
       foundMax = true;
    }

    newLs.Add(val);
}

result = newLs.ToArray();

Answer 4

    var ar = new[] { 4, 7, 9, 3, 8, 6, 4, 3, 3, 9 };
    var max = ar.Max();
    var min = ar.Min();
    var bmin = 0;
    var bmax = 0;
    var res = ar.Where(i => (i > min || 0 == bmin++) && (i < max || 0 == bmax++));