Найти пять самых больших чисел в матрице и сохранить их в массиве

var result = array.Cast<int>().OrderByDescending(x=>x).Take(5).ToArray();

var arr = new int[10, 10]
{
    {1, 2, 3, 4, 5, 6, 7, 8, 9, 10},
    {11, 12, 13, 14, 15, 16, 17, 18, 19, 20},
    {21, 22, 23, 24, 25, 26, 27, 28, 29, 30},
    {31, 32, 33, 34, 35, 36, 37, 38, 39, 40},
    {41, 42, 43, 44, 45, 46, 47, 48, 49, 50},
    {51, 52, 53, 54, 55, 56, 57, 58, 59, 60},
    {61, 62, 63, 64, 65, 66, 67, 68, 69, 70},
    {71, 72, 73, 74, 75, 76, 77, 78, 79, 80},
    {81, 82, 83, 84, 85, 86, 87, 88, 89, 90},
    {91, 92, 93, 94, 95, 96, 97, 98, 99, 100}
};
 
 
var fistBiggestNum = arr.Cast<int>().Max();
 
var secondBiggestNum = arr.Cast<int>()
                .Where(x => !Equals(x, fistBiggestNum)).Max();
 
var thirdBiggestNum = arr.Cast<int>()
    .Where(x => !Equals(x, fistBiggestNum) &
                !Equals(x, secondBiggestNum)).Max();
 
var fourthBiggestNum = arr.Cast<int>()
    .Where(x => !Equals(x, fistBiggestNum) &
                !Equals(x, secondBiggestNum) &
                !Equals(x, thirdBiggestNum)).Max();
 
var fifthBiggestNum = arr.Cast<int>()
    .Where(x => !Equals(x, fistBiggestNum) &
                !Equals(x, secondBiggestNum) &
                !Equals(x, thirdBiggestNum) &
                !Equals(x, fourthBiggestNum)).Max();
 
Console.WriteLine(fistBiggestNum);
Console.WriteLine(secondBiggestNum);
Console.WriteLine(thirdBiggestNum);
Console.WriteLine(fourthBiggestNum);
Console.WriteLine(fifthBiggestNum);
Console.ReadLine();