How to choose a number among an arrangements of numbers

Question

For example: The Numbers are 5 6 7 8 12 13 49 52 first find the smallest number (in this example: 5 ) next count about three times (in this example:8) and remove 8 from the arrangements and do this action while you arrive the last of arrangement and until just one number got not removed. so the next number after 8 will be ( 49 ) and after 49 we will arrive the last of arrangement so we must start the pathway we did before from beginning (the next number will be removed is (6 ) and the next one will be ( 13 ) the next will be ( 7 ) and the next one will be ( 5 ) and the next one will be 12 At last the number which has not been removed will be 52 . Second Example: The Arrangement of numbers are 25 34 85 79 52 13 48 77 As first example the smallest number which is chosen is ( 13 ) next count three times forward and remove this. so the number ( 25 ) will be removed and the next one is 79 which is removed the next one is 48 that will be removed the next one is 85 and the net one is 77 and the next one is 13 and the next one is 34 At last the number which has not been removed is 52 Note: Blue numbers are smallest one in each arrangements Red numbers are not been removed in each arrangements Green numbers which have been removed in each arrangements

Vulpes · Answer

I've rewritten my answer to take the input from the user. However I can't write the rest of it any simpler than it already is. What you have to remember here is that when you remove an element from the list the indices of the subsequent elements all move down by one. So after each removal instead of moving 3 elements to the right you only move 2 and if there are not enough elements left you have to wrap around to the beginning of the list again. Also when you get down to the last 2 elements you have to make sure that the new index isn't outside the list altogether. Hence the need for the line: if (index == li.Count) index = 0; using System; using System.Collections.Generic; class Program { static void Main() { Console.Write(How many numbers do you want to enter? : ); int n = int.Parse(Console.ReadLine()); Console.WriteLine(); List li = new List (n); for (int i = 0; i { Console.Write( Number {0} :  i + 1); int num = int.Parse(Console.ReadLine()); li.Add(num); } int last = GetLast(li); Console.WriteLine(
The last remaining nunmber is {0} last); Console.ReadKey(); } static int GetLast(List li) { int n = li.Count; if (n == 0) throw new ArgumentException(List can't be empty); if (n == 1) return li[0]; int min = li[0]; int index = 0; for(int i = 1; i { if(li[i] { min = li[i]; index = i; } } index += 3; while(li.Count > 1) { if (index >= li.Count) { index -= li.Count; if (index == li.Count) index = 0; } li.RemoveAt(index); index += 2; } return li[0]; } }

Joe Wilson · Answer

Thank You for your Answers for my Questions. But in this example: i want to ask the user to enter the elements of arrangement then use the method that i explained above by the way your answer is a bit complex so pleas rewrite it simply. Best Wishes Joe Wilson

Vulpes · Answer

Well it certainly works for the 2 sets of numbers you gave in your opening post as the following output shows: How many numbers do you want to enter? : 8 Number 1 : 5 Number 2 : 6 Number 3 : 7 Number 4 : 8 Number 5 : 12 Number 6 : 13 Number 7 : 49 Number 8 : 52 The last remaining number is 52 How many numbers do you want to enter? : 8 Number 1 : 25 Number 2 : 34 Number 3 : 85 Number 4 : 79 Number 5 : 52 Number 6 : 13 Number 7 : 48 Number 8 : 77 The last remaining number is 52 It also works for some other sets I tried. Have you found a set for which it doesn't work?

Joe Wilson · Answer

It isn't true though. What is going there.

Joe Wilson · Answer

Thank you very Much for your answer. Best Wishes Joe Wilson

Joe Wilson · Answer

Thank You for your answer But There are problems in the loops so Please check your answer again. Best Wishes Joe Wilson

Vulpes · Answer

Try this: using System; using System.Collections.Generic; class Program { static void Main() { var li = new List {5 6 7 8 12 13 49 52}; int last = GetLast(li); Console.WriteLine(last); li = new List {25 34 85 79 52 13 48 77}; last = GetLast(li); Console.WriteLine(last); Console.ReadKey(); } static int GetLast(List li) { int n = li.Count; if (n == 0) throw new ArgumentException(List can't be empty); if (n == 1) return li[0]; int min = li[0]; int index = 0; for(int i = 1; i { if(li[i] { min = li[i]; index = i; } } index += 3; while(li.Count > 1) { if (index >= li.Count) { index -= li.Count; if (index == li.Count) index = 0; } li.RemoveAt(index); index += 2; } return li[0]; } } The output is: 52 52

akshat goel · Answer

static void Main(string[] args) { int k = 0; Console.WriteLine(Enter the number of elements); int a = Convert.ToInt32(Console.ReadLine()); int[] arr = new int[a]; Console.WriteLine(Enter the elements); for (int i = 0; i { arr[i] = Convert.ToInt32(Console.ReadLine()); } int smallest = arr[0]; for(int i=0;i { if(arr[i] { smallest=i; } } int index; index = smallest + 3; if (index { arr[index] = Convert.ToInt32(null); } else { index = index - a; arr[index] = Convert.ToInt32(null); } for (; ; ) { index = index + 3; for (; ; ) { if ((index - 2) == Convert.ToInt32(null)) { index = index + 1; } else { break; } } for (; ; ) { if (((index - 1) == Convert.ToInt32(null))) { index = index + 1; } else { if (index { arr[index] = Convert.ToInt32(null); } else { index = index - a; arr[index] = Convert.ToInt32(null); } break; } } // var q = from x in arr // group x by Convert.ToInt32(null) into g // let count = g.Count() // select new { Count = count }; // foreach (var x in q) // { // k = k + x.Count; // } // if (k == (a - 1)) // { // break; // } } Console.WriteLine(arr[index]); } In the above code I have taken a array of numbers... making the selected number as null.. Just in the end need to find a way to count number of nulls and if no. of nulls = number of elements -1; then show the non null element...