问题求解-论题1.1:计算机为什么能解题?
问题求解 -论题1.1:计算机为什么能解题?
Computers are amazing machines,.They seem to be able to do anything.They fly aircraft and spaceships, and controlpowerstationsandhazardouschemicalplants.Companies cannolongerberunwithoutthem,andagrowingnumberof sophisticatedmedicalprocedurescannotbeperformedintheirabsence.Theyservelawyersand judgeswhoseekjudicialprecedentsinscoresofdocumentedtrials,andhelpscientistsinperformingimmenselycomplicatedand involvedmathematicalcomputations..Theyrouteandcontrol millionsoftelephonecallsinnetworksthatspancontinents.Theyexecutetaskswithenormousprecision-frommapreadingandtypesettingtographicalpictureprocessingandintegratedcircuitdesign.Theycanrelieveusofmanyboringchores,suchaskeepingameticuloustrackofhomeexpenses,andatthesametimeprovideuswithdiverseentertainmentsuchascomputergamesor computerizedmusic.Moreover, thecomputersoftodayarehard at workhelpingdesigntheevenmorepowerfulcomputersof tomorrow
Computers are amazing machines. • They seem to be able to do anything. They fly aircraft and spaceships, and control power stations and hazardous chemical plants. Companies can no longer be run without them, and a growing number of sophisticated medical procedures cannot be performed in their absence. They serve lawyers and judges who seek judicial precedents in scores of documented trials, and help scientists in performing immensely complicated and involved mathematical computations. • They route and control millions of telephone calls in networks that span continents. They execute tasks with enormous precision—from map reading and typesetting to graphical picture processing and integrated circuit design. They can relieve us of many boring chores, such as keeping a meticulous track of home expenses, and at the same time provide us with diverse entertainment such as computer games or computerized music. Moreover, the computers of today are hard at work helping design the even more powerful computers of tomorrow
实际上,计算机是什么?even the most sophisticated computerisreally only a large, well-organized volume ofbits, and moreover it can normally carry outonly a small number of extremely simpleoperations on them, such as zeroing,flipping, and testing
实际上,计算机是什么? •even the most sophisticated computer is really only a large, well-organized volume of bits, and moreover it can normally carry out only a small number of extremely simple operations on them, such as zeroing, flipping, and testing
计算机其实很笨!if this bitis 1, flipflipthisbitzerothis bitthisbity010110101101011ifthis bitflipthis bitzerothis bitis 1, flipthis bit010010100101011011010100111011ZeroingTestingFlipping
计算机其实很笨!
但是,计算机确实很神奇!Egualitytest(xy)xzero eq;flipeq;requality ontestxflipeq;testyflipeq,requalityononlytuntwice2你能将这个操作扩展到、eq比如,32位内的整数吗?Ifx=yeq=1Otherwiseeq=0我们用x0,x1..x31表示x的32个bits,用yoy1.y31表示y的32个bits
但是,计算机确实很神奇! 我们用x0,x1,.,x31表示x的32个bits,用y0,y1,.,y31表示y的32个bits