using System;

​

public class Program {

  private static char[,] ToTable(string value, int colCount) {

    if (value is null)

      throw new ArgumentNullException(nameof(value));

​

    if (colCount <= 0)

      throw new ArgumentOutOfRangeException(nameof(colCount));

​

    char[,] result = new char[

      value.Length / colCount + (value.Length % colCount == 0 ? 0 : 1), 

      colCount];

    for (int r = 0; r < result.GetLength(0); ++r) 

      for (int c = 0; c < result.GetLength(1); ++c)   

        result[r, c] = 'X';  

​

    for (int i = 0; i < value.Length; ++i)

      result[i / result.GetLength(1), i % result.GetLength(1)] = value[i];

​

    return result;

  }

  public static void Main() {

    string test =  "DELICIOUS FOOD";

    var result = ToTable(test, 5);  

    for (int r = 0; r < result.GetLength(0); ++r) {

        for (int c = 0; c < result.GetLength(1); ++c) {

            Console.Write(result[r, c]);

        }

        Console.WriteLine();

    }

  }

}