hi
with >> shift operator the bits are moved to right by the number which you mentioned and the left most bit would be added by zero's.
But >>> shift operator works the same for positive values but for negative values the left most bits would be replaced by 1's and not zero's
sorry i cannot explain with example as i dont have material right now, but i am sure about the concept that >>> shift operator on a negative numbers shifts the bits as requested and the left most bits would be filled by 1's instead of 0'2.
i will just try and find a link for you give 5 min