public static void Main()
var arr = new int[] {9,2,3,16,7,8,10,11};
FindMissingNumbers(arr, maxNum);
private static void FindMissingNumbers(int[] arr, int maxNum)
var tmpArray = new int[maxNum];
for(int i=0;i<arr.Length; i++)
for(int j=0;j<tmpArray.Length; j++)