static bool EvaluateEquation(List <MatchDigit> origEquation)
{
List <int> equationSubs = new List <int>();
int currentValue = 0;
char currentSymbol = '+';
for (int i = 0; i < origEquation.Count; i++)
{
MatchDigit currentDigit = origEquation[i];
if (currentDigit.DigitType == DigitType.Number)
{
if (currentSymbol == '+')
{
currentValue += currentDigit.ToInteger();
}
else if (currentSymbol == '-')
{
currentValue -= currentDigit.ToInteger();
}
else
{
equationSubs.Add(currentValue);
currentValue = currentDigit.ToInteger();
}
}
else
{
currentSymbol = currentDigit.ToSymbol();
}
}
equationSubs.Add(currentValue);
if (equationSubs.Count < 2)
{
return(false);
}
foreach (int subExpValue in equationSubs)
{
if (subExpValue != equationSubs.First())
{
return(false);
}
}
return(true);
}
static void Main(string[] args)
{
if (args.Length == 0)
{
Console.WriteLine("Usage: MathSolver <equation> [--verbose]");
Environment.Exit(-1);
}
else
{
var argsList = args.ToList();
if (argsList.Contains("--verbose"))
{
verbose = true;
argsList.Remove("--verbose");
}
inputEquation = argsList.FirstOrDefault();
}
if (String.IsNullOrWhiteSpace(inputEquation))
{
Console.WriteLine("An equation is required.");
Environment.Exit(-1);
}
List <MatchDigit> origEquation = ConstructEquation(inputEquation);
for (int firstDigitIndex = 0; firstDigitIndex < origEquation.Count; firstDigitIndex++)
{
MatchDigit matchDigitToRemoveFrom = origEquation[firstDigitIndex];
for (int i = 0; i < matchDigitToRemoveFrom.MatchPositions.Count; i++)
{
if (matchDigitToRemoveFrom.MatchPositions[i] == true)
{
matchDigitToRemoveFrom.MatchPositions[i] = false;
for (int secondDigitIndex = 0; secondDigitIndex < origEquation.Count; secondDigitIndex++)
{
MatchDigit matchDigitToAddTo = origEquation[secondDigitIndex];
for (int j = 0; j < matchDigitToAddTo.MatchPositions.Count; j++)
{
if (i == j)
{
continue;
}
if (matchDigitToAddTo.MatchPositions[j] == false)
{
matchDigitToAddTo.MatchPositions[j] = true;
if (matchDigitToAddTo.IsValid() && matchDigitToRemoveFrom.IsValid())
{
if (verbose)
{
Console.WriteLine(PrintEquation(origEquation, firstDigitIndex, i, secondDigitIndex, j));
}
if (EvaluateEquation(origEquation))
{
Console.WriteLine("SOLVED: " + PrintEquation(origEquation, firstDigitIndex, i, secondDigitIndex, j));
}
}
matchDigitToAddTo.MatchPositions[j] = false;
}
}
}
matchDigitToRemoveFrom.MatchPositions[i] = true;
}
}
}
Console.WriteLine("Done.");
}