/// <summary>
/// 右側計算式集合作成并返回當前新作成的計算式
/// </summary>
/// <param name="maximumLimit">計算結果最大值</param>
/// <param name="leftFormulaAnswer">左側新作成計算式的結果值</param>
/// <param name="signFunc">運算符取得用的表達式</param>
/// <returns>新作成的計算式</returns>
private Formula MakeRightFormulas(int maximumLimit, int leftFormulaAnswer, Func <SignOfOperation> signFunc)
{
IArithmetic strategy = CalculateManager(signFunc());
// 計算式作成（依據左邊算式的答案推算右邊的算式）
Formula formula = strategy.CreateFormulaWithAnswer(new ArithmeticParameter()
{
MaximumLimit = maximumLimit,
QuestionType = QuestionType.Default,
MinimumLimit = 0
}, leftFormulaAnswer);
return(formula);
}