static private IEnumerable <int[]> GeneratePossibleCombinations(ExpressionMinigameSettings inLevel)
{
// Bitwise subset mask algorithm from:
// https://www.topcoder.com/community/data-science/data-science-tutorials/a-bit-of-fun-fun-with-bits/
int[] combination = new int[inLevel.NumValueSlots];
int mask = (1 << combination.Length) - 1;
while ((mask & (1 << inLevel.Chickens.Length)) == 0)
{
int chickenIndex = 0;
for (int i = 0; i < inLevel.Chickens.Length; ++i)
{
int chickenBit = 1 << i;
if ((chickenBit & mask) > 0)
{
combination[chickenIndex++] = inLevel.Chickens[i];
}
}
yield return(combination);
int lowBit = mask & ~(mask - 1);
int lowZero = (mask + lowBit) & ~mask;
mask |= lowZero;
mask &= ~(lowZero - 1);
mask |= (lowZero / lowBit / 2) - 1;
}
}
static private bool ValidateLevel(JSONNode inLevelJSON)
{
ExpressionMinigameSettings level = ExpressionMinigameSettings.FromJSON(inLevelJSON, ExpressionMinigameCategories.Single);
bool bCanSolve = false;
// Horrible, brute force solving
foreach (int[] combination in GeneratePossibleCombinations(level))
{
if (CanReachTarget(level, combination))
{
bCanSolve = true;
break;
}
}
if (!bCanSolve)
{
UnityEngine.Debug.LogWarningFormat("Unsolvable: {0}", inLevelJSON.ToFormattedString());
EditorUtility.DisplayDialog("Unsolvable!", "Unable to solve level generated with:\n" + inLevelJSON.ToFormattedString(), "OK");
}
return(bCanSolve);
}
static private bool CanReachTarget(ExpressionMinigameSettings inLevel, int[] inValues)
{
if (inLevel.FixedOperator)
{
if (inLevel.Operator == OperatorType.Add)
{
int current = 0;
foreach (int chicken in inValues)
{
current += chicken;
}
return(current == inLevel.Value);
}
else
{
for (int i = 0; i < inValues.Length; ++i)
{
int current = 0;
for (int chickenIndex = 0; chickenIndex < inValues.Length; ++chickenIndex)
{
if (chickenIndex == i)
{
current += inValues[chickenIndex];
}
else
{
current -= inValues[chickenIndex];
}
}
if (current == inLevel.Value)
{
return(true);
}
}
}
}
else
{
for (int i = 0; i < (int)Math.Max(inValues.Length, 2); ++i)
{
int current = 0;
for (int chickenIndex = 0; chickenIndex < inValues.Length; ++chickenIndex)
{
if (chickenIndex == i)
{
current -= inValues[chickenIndex];
}
else
{
current += inValues[chickenIndex];
}
}
if (current == inLevel.Value)
{
return(true);
}
}
}
return(false);
}
