protected override void Solve(out string answer)
{
var testedRange = Enumerable.Range(1, 28123).AsParallel();
long summator = 0;
//Parallel.ForEach()
testedRange.ForAll(number =>
{
NumberDivisor numberDivisor = new NumberDivisor();
bool hasBeenWrittenAsSumOfTwoAbundantNumbers = false; //Will be set to true only if at least one sum can be expressed using abundant numbers.
long midpoint = (number / 2) + 1;
for (int i = 1; i <= midpoint; i++)
{
#region Get left and right portions of the number in all combinations
var left = i;
var right = number - left;
#endregion
var leftAbundancyType = numberDivisor.IsAbundantOrDeficientOrPerfect(left);
var rightAbundancyType = numberDivisor.IsAbundantOrDeficientOrPerfect(right);
if (leftAbundancyType == AbundancyType.Abundant && rightAbundancyType == AbundancyType.Abundant)
{
hasBeenWrittenAsSumOfTwoAbundantNumbers = true;
break;
}
}
if (!hasBeenWrittenAsSumOfTwoAbundantNumbers)
{
lock (this) summator += number; //Increase the sum if combination of 2 abundant numbers could not be found.
}
});
answer = string.Format("Sum of all the positive integers which cannot be written as the sum of two abundant numbers is {0}.", summator);
}
public void TestPerfects()
{
DateTime start = DateTime.Now;
long temp = 28;
NumberDivisor numberDivisor = new NumberDivisor();
var sumDivisors = numberDivisor.CalculateSumOfProperDivisors(temp);
var is28Abundant = numberDivisor.IsAbundantOrDeficientOrPerfect(temp);
var is12Abundant = numberDivisor.IsAbundantOrDeficientOrPerfect(12);
var is57Abundant = numberDivisor.IsAbundantOrDeficientOrPerfect(57);
var elapsedTime = DateTime.Now - start;
var sb = new StringBuilder();
sb.AppendFormat("Elapsed computation time: {0}. Sum of properDivisors of {1} = {2}.", elapsedTime, temp, sumDivisors); sb.AppendLine();
sb.AppendFormat("Number {0} is {1}.", temp, is28Abundant); sb.AppendLine();
sb.AppendFormat("Number {0} is {1}.", 12, is12Abundant); sb.AppendLine();
sb.AppendFormat("Number {0} is {1}.", 57, is57Abundant); sb.AppendLine();
Answer = sb.ToString();
}