Cell

public abstract class Cell
        {
            protected string cell;

            public virtual int Calculate()
            {
                return 0;
            }

            public virtual int GetValue()
            {
                return 0;
            }
            public override string ToString()
            {
                return cell;
            }

            public string GetCell() { return cell; }
        }

        public class ValueCell : Cell
        {
            private int value;
            public ValueCell(string cell, int value) : base()
            {
                this.cell = cell;
                this.value = value;
            }

            public override int GetValue() { return value; }
            public void SetValue(int value) { this.value = value; }

            public override string ToString()
            {
                return $"{cell}:{value}";
            }
        }

        public abstract class FunctionCell : Cell
        {
            public virtual string FunctionName()
            {
                return "N/A";
            }
        }

        public class SumCell : FunctionCell
        {
            private ValueCell[] valueCells;
            public SumCell(string cell, Cell[] valueCells) : base()
            {
                this.cell = cell;
                this.valueCells = new ValueCell[valueCells.Length];
                for(int i = 0; i < valueCells.Length; i++)
                {
                    this.valueCells[i] = (ValueCell)valueCells[i];
                }
            }
            public override string ToString()
            {
                string cellsString = "";
                for (int i = 0; i < valueCells.Length; i++)
                    cellsString = cellsString + $" {valueCells[i].GetCell()}";
                return $"{cell}:SUM({cellsString})";
            }

            public override int Calculate()
            {
                int sum = 0;
                for (int i = 0; i < valueCells.Length; i++)
                    sum += valueCells[i].GetValue();
                return sum;
            }

            public override string FunctionName()
            {
                return "Sum";
            }
        }

        public class MinCell : FunctionCell
        {
            private ValueCell[] valueCells;
            public MinCell(string cell, ValueCell[] valueCells) : base()
            {
                this.cell = cell;
                this.valueCells = valueCells;
            }
            public override string ToString()
            {
                string cellsString = "";
                for (int i = 0; i < valueCells.Length; i++)
                    cellsString = cellsString + $" {valueCells[i].GetCell()}";
                return $"{cell}:MIN({cellsString})";
            }

            public override int Calculate()
            {
                int min = Math.Min(valueCells[0].GetValue(), valueCells[1].GetValue());
                for(int i = 2; i < valueCells.Length; i++)
                    min = Math.Min(min, valueCells[i].GetValue());
                return min;
            }

            public override string FunctionName()
            {
                return "Min";
            }
        }

        public class MaxCell : FunctionCell
        {
            private Cell[] valueCells;
            public MaxCell(string cell, Cell[] valueCells) : base()
            {
                this.cell = cell;
                this.valueCells = new ValueCell[valueCells.Length];
                for(int i = 0; i < valueCells.Length; i++)
                {
                    if (valueCells[i] is ValueCell)
                        this.valueCells[i] = (ValueCell)valueCells[i];
                    else
                    {
                        ValueCell temp = new ValueCell(valueCells[i].GetCell(), valueCells[i].Calculate());
                        this.valueCells[i] = temp;
                    }

                }

            }
            public override string ToString()
            {
                string cellsString = "";
                for (int i = 0; i < valueCells.Length; i++)
                    cellsString = cellsString + $" {valueCells[i].GetCell()}";
                return $"{cell}:MAX({cellsString})";
            }

            public override int Calculate()
            {
                int max = Math.Max(valueCells[0].GetValue(), valueCells[1].GetValue());
                for (int i = 2; i < valueCells.Length; i++)
                    max = Math.Max(max, valueCells[i].GetValue());
                return max;
            }

            public override string FunctionName()
            {
                return "Max";
            }
        }

        public class AvgCell : FunctionCell
        {
            private ValueCell[] valueCells;
            public AvgCell(string cell, ValueCell[] valueCells) : base()
            {
                this.cell = cell;
                this.valueCells = valueCells;
            }
            public override string ToString()
            {
                string cellsString = "";
                for (int i = 0; i < valueCells.Length; i++)
                    cellsString = cellsString + $" {valueCells[i].GetCell()}";
                return $"{cell}:AVG({cellsString})";
            }
            public override int Calculate()
            {
                int sum = 0;
                int count = 0;
                for(int i = 0; i < valueCells.Length; i++)
                {
                    sum += valueCells[i].GetValue();
                    count++;
                }
                return sum / count;
            }

            public override string FunctionName()
            {
                return "Avg";
            }
        }