CS-APP--SolutionManual软件开发书籍.pdf

ComputerSystems:AProgrammer’sPerspective Instructor’sSolutionManual 1 ’Hallaron December4,2003 1Copyright c2003,,’. 2 Chapter1 SolutionstoHomeworkProblems Thetextusestwodifferentkindsofexercises: ,withexplanatory . simpledrillstomulti-weeklabsandaredesignedforinstructorstogiveasassignmentsortouseas recitationexamples. Thisdocumentgivesthesolutionstothehomeworkproblems. :puterSystems :RepresentingandManipulatingInformation : Thisexerciseshouldbeastraightforwardvariationontheexistingcode. code/data/show- 1voidshow_short(shortintx) 2{ 3 show_bytes((byte_pointer)&x,sizeof(shortint)); 4} 56voidshow_long(longintx) 7{ 8 show_bytes((byte_pointer)&x,sizeof(long)); 9} 1 2 10 11voidshow_double(doublex) 12{ 13 show_bytes((byte_pointer)&x,sizeof(double)); 14} code/data/show- : valuesforthemostandleast-signi?. ?rstbyteandconvertittoan -endianmachineand1onalittle-- 1intis_little_endian(void) 2{ 3 /*MSB=0,LSB=1*/ 4 intx=1; 56 /*ReturnMSBwhenbig-endian,LSBwhenlittle-endian*/ 7 return(int)(*(char*)&x); 8} code/data/show- : ?0xFFisaway togenerateamaskthatselectsallbuttheleastsigni?cantbytethatworksforanywordsize. (x&0xFF)|(y&?0xFF) : Theseexercisesrequirethinkingaboutthelogicaloperatio