Anonymous Threat

using Microsoft.VisualBasic;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace _1.Anonymous_Treat
{
    class Program
    {
        static void Main(string[] args)
        {
            List<string> input = Console.ReadLine().Split(' ').ToList();
            string[] command = Console.ReadLine().Split(' ').ToArray();
            while (command[0] != "3:1")
            {
                if (command[0] == "merge")
                {
                    StringBuilder str = new StringBuilder();
                    int startIndex = int.Parse(command[1]);
                    int endIndex = int.Parse(command[2]);
                    if (startIndex <= input.Count-1)
                    {
                        if (startIndex < 0)
                        {
                            startIndex = 0;
                        }
                        if (endIndex >= input.Count-1)
                        {
                            endIndex = input.Count - 1;
                        }
                        for (int i = startIndex; i <= endIndex; i++)
                        {
                            str.Append(input[i]);
                        }
                        for (int i = endIndex; i >= startIndex; i--)
                        {
                            input.RemoveAt(i);
                        }
                        string merged = str.ToString();
                        input.Insert(startIndex, merged);
                    }
                }
                else if (command[0] == "divide")
                {
                    List<string> inner = new List<string>();
                    int index = int.Parse(command[1]);
                    int partition = int.Parse(command[2]);
                    if(partition > 0 )
                    {
                        string strToDivide = input[index].ToString();
                        int counter = 0;
                        StringBuilder str = new StringBuilder();
                        for (int i = 0; i < strToDivide.Length; i++)
                        {
                            if (counter == (int)strToDivide.Length / partition)
                            {
                                if (i == strToDivide.Length - strToDivide.Length / partition)
                                {
                                    inner.Add(str.ToString());
                                    counter = 0;
                                    str.Clear();
                                    for (int j = i; j < strToDivide.Length; j++)
                                    {
                                        str.Append(strToDivide[j]);
                                    }
                                    inner.Add(str.ToString());
                                    break;
                                }
                                else
                                {
                                    inner.Add(str.ToString());
                                    counter = 0;
                                    str.Clear();
                                    str.Append(strToDivide[i]);
                                    counter++;
                                }
                            }
                            else
                            {
                                str.Append(strToDivide[i]);
                                counter++;
                            }
                        }
                        input.RemoveAt(index);
                        input.InsertRange(index, inner);
                    }
                }
                command = Console.ReadLine().Split(' ').ToArray();
            }
            Console.WriteLine(string.Join(" ", input));
        }
    }
}