/**
* Calculates the maintenance cost of a number of signals.
* @param num Number of signals.
* @return Total cost.
*/
public static Money SignalMaintenanceCost(uint num)
{
return((_price[PR_INFRASTRUCTURE_RAIL] * 15 * num * (1 + MathFuncs.IntSqrt(num))) >>
8); // 1 bit fraction for the multiplier and 7 bits scaling.
}