Rows

using System;

namespace CSLightFirst
{
    class Program
    {
        static void Main()
        {
            int picturesCount = 52;
            int picturesInRow = 3;
            int rowCount = picturesCount / picturesInRow;
            int remainingPictures = picturesCount % picturesInRow;

            Console.WriteLine($"Заполненных рядов: {rowCount}\n" +
                              $"Картинок сверх меры: {remainingPictures}");
        }
    }
}