public RememberedPathStates(int nUnits)
 {
     LastPathState.Capacity = nUnits;
     for (int n = 0; n < nUnits; n++)
     {
         LastPathState.Add(null);
     }
 }
        public void RemoveRange(int[] unitIndexes)
        {
            var nRemoved = 0;

            foreach (var index in unitIndexes)
            {
                LastPathState.RemoveAt(index - nRemoved);
                nRemoved++;
            }
        }