/// <summary>
/// 生成S盒选择项的行号列号
/// </summary>
/// <param name="input">输入（48位）</param>
/// <param name="firstBit">第一位位置（从此位置向后取6位）</param>
/// <param name="row">产生的行号</param>
/// <param name="col">产生的列号</param>
private static void GenerateRowAndColumnNumber(BitArray input, int firstBit, out int row, out int col)
{
int lastBit = firstBit + 5;
BitArray columnArray = new BitArray(4);
BitArray rowArray = new BitArray(2);
rowArray[0] = input[firstBit];
rowArray[1] = input[lastBit];
columnArray[0] = input[firstBit + 1];
columnArray[1] = input[firstBit + 2];
columnArray[2] = input[firstBit + 3];
columnArray[3] = input[firstBit + 4];
row = rowArray.ToInt32();
col = columnArray.ToInt32();
}