unstablePVExtraTime = curChanges * (optimumSearchTime / 2)

+ prevChanges * (optimumSearchTime / 3);

{

/* We support four different kind of time controls:

int hypMTG, hypMyTime, t1, t2;

// Read uci parameters

int emergencyMoveHorizon = Options["Emergency Move Horizon"].value<int>();

int emergencyBaseTime = Options["Emergency Base Time"].value<int>();

int emergencyMoveTime = Options["Emergency Move Time"].value<int>();

int minThinkingTime = Options["Minimum Thinking Time"].value<int>();

// Initialize to maximum values but unstablePVExtraTime that is reset

unstablePVExtraTime = 0;

optimumSearchTime = maximumSearchTime = myTime;

// We calculate optimum time usage for different hypothetic "moves to go"-values and choose the

// minimum of calculated search time values. Usually the greatest hypMTG gives the minimum values.

for (hypMTG = 1; hypMTG <= (movesToGo ? Min(movesToGo, MoveHorizon) : MoveHorizon); hypMTG++)

{

// Calculate thinking time for hypothetic "moves to go"-value

hypMyTime = Max(myTime + (hypMTG - 1) * myInc - emergencyBaseTime - Min(hypMTG, emergencyMoveHorizon) * emergencyMoveTime, 0);

t1 = minThinkingTime + remaining<OptimumTime>(hypMyTime, hypMTG, currentPly);

t2 = minThinkingTime + remaining<MaxTime>(hypMyTime, hypMTG, currentPly);

optimumSearchTime = Min(optimumSearchTime, t1);

maximumSearchTime = Min(maximumSearchTime, t2);

}

if (Options["Ponder"].value<bool>())

optimumSearchTime += optimumSearchTime / 4;

// Make sure that maxSearchTime is not over absoluteMaxSearchTime

optimumSearchTime = Min(optimumSearchTime, maximumSearchTime);

{

const float TMaxRatio = (T == OptimumTime ? 1 : MaxRatio);

const float TStealRatio = (T == OptimumTime ? 0 : StealRatio);

int thisMoveImportance = move_importance(currentPly);

int otherMovesImportance = 0;

for (int i = 1; i < movesToGo; i++)

otherMovesImportance += move_importance(currentPly + 2 * i);

float ratio1 = (TMaxRatio * thisMoveImportance) / float(TMaxRatio * thisMoveImportance + otherMovesImportance);

float ratio2 = (thisMoveImportance + TStealRatio * otherMovesImportance) / float(thisMoveImportance + otherMovesImportance);

return int(floor(myTime * Min(ratio1, ratio2)));