úÎP x      Safe-InferedBA vector clock is, conceptually, an associtive list sorted by the 5 value of the key, where each key appears only once. The empty vector clock. &A vector clock with a single element. -Insert each entry in the list one at a time. Is the vector clock empty? +The number of entries in the vector clock. 0Lookup the value for a key in the vector clock. 8Is the given key a key in an entry of the vector clock? ?Delete an entry from the vector clock. If the requested entry  does not exist, does nothing. 'Insert or replace the entry for a key. *Combine two vector clocks entry-by-entry. &The maximum of the two vector clocks. ,The relation between the two vector clocks. 0Check whether the vector clock is valid or not.           vector-clock-0.1.0Data.VectorClock VectorClockempty singletonfromListnullsizelookupmemberdeleteinsertcombinemaxrelationvalid$fBinaryVectorClock$fShowVectorClock