/// <summary>
/// Execute arithmetic operation with operands op1 and op2
/// </summary>
/// <param name="op1">first operand</param>
/// <param name="op2">second operand</param>
/// <param name="operator">arithmetic operation</param>
/// <returns>A result of arithmetic operation with bigNumbers op1 and op2.</returns>
private string ApplyOperation(string op1, string op2, string @operator)
{
op1 = StringNumber.RemoveSpaces(op1);
op2 = StringNumber.RemoveSpaces(op2);
op1 = StringNumber.RemoveUnnecessaryZeros(op1);
op2 = StringNumber.RemoveUnnecessaryZeros(op2);
string norm_result = null;
if ((norm_result = ProcessNeutralOperands(op1, op2, @operator)) != null)
{
return(norm_result);
}
int p1 = StringNumber.GetPrecisionNumber(op1);
int p2 = StringNumber.GetPrecisionNumber(op2);
int prec = (p1 > p2) ? p1 : p2;
BigInteger n1 = BigInteger.Parse(StringNumber.UpPowerOfNumber(op1, prec));
BigInteger n2 = BigInteger.Parse(StringNumber.UpPowerOfNumber(op2, prec));
BigInteger?result = @operator switch
{
"+" => BigInteger.Add(n1, n2),
"*" => BigInteger.Multiply(n1, n2),
"-" => BigInteger.Subtract(n1, n2),
"/" => null,
_ => null
};
if (result.HasValue == false && @operator == "/")
{
return(StringNumber.DivideRationalNumbers(n1, n2));
}
else if (result.HasValue == false)
{
return("Err");
}
prec = @operator switch
{
"*" => prec + prec,
"+" => prec,
"-" => prec,
_ => 0
};
norm_result = StringNumber.DownPowerOfNumber(result.ToString(), prec);
return(StringNumber.RemoveUnnecessaryZeros(norm_result));
}
