public static NaturalNumber CalculateExpression(string expression)
{
var expressionParts = expression.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (expressionParts.Length != 3)
{
throw new InvalidDataException("Invalid expression!");
}
var firstNumber = new NaturalNumber(expressionParts[0]);
var secondNumber = new NaturalNumber(expressionParts[2]);
var operation = expressionParts[1];
return GetResult(operation, firstNumber, secondNumber);
}
public static NaturalNumber CalculateExpression(string expression)
{
var expressionParts = expression.Split(new[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
if (expressionParts.Length != 3)
{
throw new InvalidDataException("Invalid expression!");
}
var firstNumber = new NaturalNumber(expressionParts[0]);
var secondNumber = new NaturalNumber(expressionParts[2]);
var operation = expressionParts[1];
return(GetResult(operation, firstNumber, secondNumber));
}
private static NaturalNumber GetResult(string operation, NaturalNumber firstNaturalNumber, NaturalNumber secondNaturalNumber)
{
NaturalNumber result;
switch (operation)
{
case "+":
result = firstNaturalNumber + secondNaturalNumber;
break;
case "-":
result = firstNaturalNumber - secondNaturalNumber;
break;
case "*":
result = firstNaturalNumber*secondNaturalNumber;
break;
default:
throw new InvalidOperationException("Invalid operation");
}
return result;
}
private static NaturalNumber GetResult(string operation, NaturalNumber firstNaturalNumber, NaturalNumber secondNaturalNumber)
{
NaturalNumber result;
switch (operation)
{
case "+":
result = firstNaturalNumber + secondNaturalNumber;
break;
case "-":
result = firstNaturalNumber - secondNaturalNumber;
break;
case "*":
result = firstNaturalNumber * secondNaturalNumber;
break;
default:
throw new InvalidOperationException("Invalid operation");
}
return(result);
}
public static NaturalNumber operator *(NaturalNumber a, NaturalNumber b)
{
var result = new NaturalNumber(a.Arabic * b.Arabic);
return(result);
}
public static NaturalNumber operator -(NaturalNumber a, NaturalNumber b)
{
if (a.Arabic - b.Arabic <= 0)
{
throw new InvalidOperationException("Result outside the set of natural numbers");
}
var result = new NaturalNumber(a.Arabic - b.Arabic);
return result;
}
public static NaturalNumber operator +(NaturalNumber a, NaturalNumber b)
{
var result = new NaturalNumber(a.Arabic + b.Arabic);
return result;
}
