question: public static < T > EfficiencyRun determineEfficiency ( Map < T , T > cache , List < T > workingSet ) { int hits = 0 ; for ( T key : workingSet ) { if ( cache . get ( key ) == null ) { cache . put ( key , key ) ; } else { hits ++ ; } } return EfficiencyRun . of ( hits , workingSet . size ( ) ) ; }
target:  Determines the hit/miss rate of a cache.