public void GetFactorial_Returns_Factorial_Result()
{
var number = 10;
var expected = Enumerable.Range(1, number).Aggregate(1, (factorial, number) => factorial * number);
LargeNumberMath.GetFactorial(number).Should().Be(expected.ToString());
}
/// <summary>
/// Run solution for problem 20.
/// </summary>
/// <param name="factorialInput">Factorial input.</param>
/// <returns>Sum of factorial result's digits.</returns>
public static int Run(int factorialInput)
{
return(LargeNumberMath.GetFactorial(factorialInput).ToCharArray().Aggregate(0, (sum, digit) =>
{
return sum + int.Parse(digit.ToString());
}));
}
public void GetProduct_Returns_Product_of_Two_Numbers()
{
var number1 = 25;
var number2 = 24;
LargeNumberMath.GetProduct(number1.ToString(), number2.ToString())
.Should().Be((number1 * number2).ToString());
}
public void GetDifference_Returns_Difference_Of_Two_Numbers_That_Results_In_A_Negative_Number()
{
var number1 = 103;
var number2 = 6983;
LargeNumberMath.GetDifference(number1.ToString(), number2.ToString())
.Should().Be((number1 - number2).ToString());
}
public void GetDifference_Returns_Difference_Of_Two_Numbers_That_Results_In_Zero()
{
var number1 = 888;
var number2 = 888;
LargeNumberMath.GetDifference(number1.ToString(), number2.ToString())
.Should().Be((number1 - number2).ToString());
}
public void GetDifference_Returns_Difference_Of_Two_Numbers()
{
var number1 = 348002001;
var number2 = 968;
LargeNumberMath.GetDifference(number1.ToString(), number2.ToString())
.Should().Be((number1 - number2).ToString());
}
public void GetSum_Returns_Sum_of_Two_Numbers()
{
var number1 = 64;
var number2 = 25;
LargeNumberMath.GetSum(number1.ToString(), number2.ToString())
.Should().Be((number1 + number2).ToString());
}
/// <summary>
/// Run solution for problem 48.
/// </summary>
/// <param name="rangeThreshold">Range threshold.</param>
/// <returns>
/// Last 10 digits of the sum of the series up to <paramref name="rangeThreshold"/> of self
/// powers.
/// </returns>
public static string Run(int rangeThreshold)
{
var sum = "0";
for (var i = 1; i <= rangeThreshold; i += 1)
{
sum = LargeNumberMath.GetSum(sum, new Exponent(i, i).ToInt());
}
return(sum[^ 10..]);
