System.Text.RegularExpressions.RegexFCD.PushInt C# (CSharp) Method

        private void PushInt(int I)
        {
            if (_intDepth >= _intStack.Length)
            {
                int[] expanded = new int[_intDepth * 2];

                Array.Copy(_intStack, 0, expanded, 0, _intDepth);

                _intStack = expanded;
            }

            _intStack[_intDepth++] = I;
        }