public NumberMove[] Solve()
{
if (_totalSum % _k != 0)
{
return(null);
}
for (BoxId boxId = 0; boxId < _k; boxId++)
{
_moveGroups[boxId] = FindMoveGroups(_boxes[boxId]);
}
var resultMoveGroups = new List <MoveGroup>(_k);
if (!TryFindResultMoveGroups(BoxGroup.Empty, resultMoveGroups))
{
return(null);
}
var result = new NumberMove[_k];
foreach (var moveGroup in resultMoveGroups)
{
ExpandMoveGroup(moveGroup, result);
}
return(result);
}
private void ExpandMoveGroup(MoveGroup moveGroup, NumberMove[] result)
{
var targetBoxId = moveGroup.BoxId;
var searchFor = moveGroup.InitialMoveNumber;
while (true)
{
searchFor = (int)(_targetSum - (_boxes[targetBoxId].Sum - searchFor));
if (searchFor == moveGroup.InitialMoveNumber)
{
break;
}
var sourceBoxId = _numberToBoxMap[searchFor];
result[sourceBoxId] = new NumberMove(searchFor, targetBoxId);
targetBoxId = sourceBoxId;
}
result[moveGroup.BoxId] = new NumberMove(moveGroup.InitialMoveNumber, targetBoxId);
}
