C语言英文精选Chapter-10ppt课件

chapter10STRUCTURESANDUNIONSAstructureisacollectionofoneormorevariables,possiblyofdifferenttypes,whicharetreatedasaunitinsteadofasseparateentities.10.1structuredefinition10.2structurevariablescitingandinitialization10.3structurearray10.4structurepointer10.5linkdispoing---applicationofstructurepointer10.6unionandenumeration10.7typedef10.1STRUCTURETYPEANDDECLARATIONOFSTRUCTUREVARIABLESTHESTRUCTURETYPE,INCLANGUAGE，isthecounterpartas“record”inotheradvancedlanguage.一、questionemergingSTUDENTSCORESMANAGETABLECANOTDEALWITH2DARRAYSDIFFERENTTYEPES！1001ZhangXinM2087911002WangLiF2098961003ChenFongM2186901004LiXiaopenM207786numnamesexagescore1score2二、structuretypedeclarationCommonusage：structstructuretypename{datatypemember1;datatypemember2;…………datatypemembern;};structstudent{intnum;charname[20];charsex;intage;floatscore1;floatscore2;};Typenamenumnamesexagescore1score2structstudentdemonstration：1、therulestoname“structuretypename”and“membername”,aresamewiththevariables’.2、thedefinitionsofvariablescanbeseperatedorinasamelineliketheinstancebeloweg.structdate{intyear,month,day;};3、thedefinitionsofvariablescouldbebasictypesoranotherstructuretypewhichhasbeendeclarated.eg.thetype”birthday”intheeg.Ofstructuretypestd_infoisadefinitedstructuretype--date三、STRUCTUREVARIABLESDECLARATIONStructuretype（userdefinition）Standarttype（systemdefinition）1、indirectdeclaration──firstdeclarethestructuretype,thenthestructurevariablesThesameusagestructstudent{intnum;charname[20];charsex;intage;floatscore1;floatscore2;};structstudentstu1,stu2;numnamesexagescore1score2stu12、directdeclaration(1)definitethestructurevariable,whendefinitingthestructuretype；(2)definitethestructurevariabledirectly；(1)structstudent{intnum;charname[20];……floatscore2;}stu1,stu2;(2)struct{intnum;charname[20];……floatscore2;}stu1,stu2;3、demonstration(1)differstructuretypeandvariable,whicharecompletelydifferentconception,justastypeintandvariableofint(2)membernamesinstructure,maybesameasothervariablesinprogram,standfordifferentobjects[eg10.1]creatastructurerefferingtobasicinformationofastudenttostorethedetailsofastudentstructdate/*datastructuretypemadeofyear,monthandday*/{intyear;intmonth;intday;};structstd_info/*studentinformationstructuretype*/{intnum;/*madeofname,sex,birthday,etc*/charname[12];charsex;structdatebirthday;floatscore1,score2;};numnamesexscore1score2birthdayyearmonthday10.2CITINGANDINITIALIZATIONSOFSTUCTUREVARIABLES[例10.2]makeuseoftheformerstucturetypestructstd_info，todefiniteastructuretypestutostoreandprintthestudentdetails#include“struct.h”structstd_infostu={1002,”ZhangSan”,‘M’,{1980,9,20},98.2,86.5};main(){printf("No:%d\n",stu.num);printf("Name:%s\n",stu.name);printf("Sex:%c\n",stu.sex);printf("Birthday:%d-%d-%d\n",stu.birthday.year,stu.birthday.month,stu.birthday.day);}numnamesexscore1score2birthdayyearmonthdayresult：No:1002Name:ZhangSanSex:MBirthday:1980-9-201、INITIALIZATIONSOFSTUCTUREvariablestructtypestruct_variable={initialvaluelist}eg，structstd_infostu={“000102”,”ZhangSan”,‘M’,{1980,9,20}};note：datatypeofinitialvalueshouldbeconsistentwiththemembersinstructurevariable,ortherewillbeerror.2、citingrulesofstructurevariablememberoperator“.”whilecitingthememberinstructure,useoperator”.”;citingformat:structurevariable.membereg,stu.num；stu.name,etc。NOTE：ifamemberitselfisastructuretype,amultilevelmemberoperationisneededtocitethelowestmember.Expandingformat：structurevariable.member.child-member.….LowestmemberEg.：stu.birthday.yearstu.birthday.monthstu.birthday.daybetakingthelowestmemberisequaltocommonvariableofthesametype.10.3STRUCTUREARRAYSStructurearrays：anarraymadebystructuretypedatawhichisaselementinstructure.Everyarrayelement:includeallmembersofstructure[例10.3]usestructurearraytostoreandprintthestudentscoresmanagetablebelow.stu[0]stu[1]stu[2]stu[3]1001ZhangXinM2087911002WangLiF2098961003ChenFongM2186901004LiXiaopenM207786numnamesexagescore1score2structstudent/*laythedefinitionofstructuretypeoutsidefunction*/{intnum;charname[12];charsex;intage;floatscore1;floatscore2;};structstdentstu[4]={{1001,”ZhangXin”,’M’,20,87,91},{1002,”WangLi”,‘F’,20,98,96},{1003,”ChenFong”,’M’,21,86,90},{1004,”LiXiaopen”,‘M’,20,77,86}};Storeinfile“struct.h”#include"struct.h”main(){inti;/*printlisthead,"□“standsforonebackspace*/printf("No.□□Name□□□□□□□□Sex□Age□soc1□sco2\n");/*outputbasicdetailsof4students*/for(i=0;i<4;i++){printf("%-5d",stu[i].num);printf("%-12s",stu[i].name);printf("%-4c",stu[i].sex);printf("%-4d",stu[i].age);printf("%-5.1f",stu[i].score1);printf("%-5.1f\n",stu[i].score2);}}Runningresult：No.NameSexAgesoc1sco21001ZhangXinM2087911002WangLiF2098961003ChenFongM2186901004LiXiaopenM207786[eg10.4]usearraysofstructureasfuntionparameters#include"struct.h"voidprint_stulist(structstudentstu[]){inti;printf("No.NameSexAgesoc1sco2\n");for(i=0;i<4;i++){printf("%-5d",stu[i].num);printf("%-12s",stu[i].name);printf("%-4c",stu[i].sex);printf("%-4d",stu[i].age);printf("%-5.1f",stu[i].score1);printf("%-5.1f\n",stu[i].score2);}}UseArrayofstructureasformalparametervoidsort(structstudentst[]){inti,j;structstudenttemp;for(i=0;i<4-1;i++)for(j=i+1;j<4;j++)if(st[i].score1membernamethoughts：howtoinputeverymemberofstu[i]bykeyboard?10.5linklistdisposing──applicationofstructurepointer10.5.1linklistoverview一．Dynamicdatastructureelementnumberfluctuatesbyprogramrunning.cf.datastructureofstaticstate（eg.array）,confirmingitssizewhendefiniting.二．Dynamicdatastructureimplementinvirtueof：1、pointerpointstostructuretype2、structuretypeincludingpointerdatalinklist：asimpledynamicdatastructure.head3125NULL10.5.2creatinglinklist一、descriptionoflinklistnodestructureeg.structnode{intnum;/*dataarea*/structnode*next;/*pointerarea*/};二、functionofdisposinglinklist1、malloc——applymemorystoragevoid*malloc(unsignedintsize)eg.structnode*p;p=(structnode*)malloc(sizeof(structnode));numnextp2、free——setstorageareafreevoidfree(void*p)三、createlinklist[例10.6]accordingtoaseriesofnonnegativeintegers,inputbykeyboard,tocreatealinklist,andoutputthevalueofeverydataareabyordereg：input13250，createlinklistsuchas：3125NULLhead1325NULLhead/*1.creatnewnode，pointedbyheadpointer*/head=(structnode*)malloc(LEN);last=head;/*tailpointerpointstonodeoftail*/headlast/*2.inputx;createnewnodep;storextonumareaofnodep*/scanf("%d",&x);p=(structnode*)malloc(LEN);p->num=x;/*3.addptothelinklisttail*/last->next=p;1headlastp1headplast/*4.lastmovebackwards*/last=p;1headlastpRepeat2~4，whenx≤0132head5NULLlast/*setpointerareaNULLwhichwaspointedbytailnodepointer，headpointermovebackwards(deletingheadnode)*/last->next=NULL;head=head->next;main(){structnode*head,*p,*last;intx;head=(structnode*)malloc(LEN);last=head;while(1){scanf("%d",&x);if(x<=0)break;p=(structnode*)malloc(LEN);p->num=x;last->next=p;last=p;}last->next=NULL;head=head->next;#defineNULL0#defineLENsizeof(structnode)structnode{intnum;structnode*next;};p=head;head=head->next;free(p);132head5NULL/*outputlinklist*/printf(“dataofthelinklistare:”)p=head;while(p!=NULL){printf("%5d",p->num);p=p->next;}printf("\n");getch();}Runningresult：13250dataofthelinklistare:1325Q：make2functionsforcreatinglinklistandoutputlinklist：1.structnode*creat(void)2.voidprint(structnode*head)structnode*creat(void)/*createlinklistfunction*/{structnode*head,*p,*last;intx;head=(structnode*)malloc(LEN);last=head;while(1){scanf("%d",&x);if(x<=0)break;p=(structnode*)malloc(LEN);p->num=x;last->next=p;last=p;}last->next=NULL;p=head;head=head->next;free(p);return(head);}2、outputlinklist1、installlinklist四、realizingbyfunction：voidprint(structnode*head)/*outputlinklistfunction*/{structnode*p;p=head;while(p!=NULL)/*traversingthelinklist*/{printf("%5d",p->num);p=p->next;}printf("\n");getch();}main(){structnode*head;printf("inputdatatocreatlinklist(endby<=0):\n");head=creat();printf("thedataoflinklist:\n");print(head);}Q：computingthemaxinumandmininumofthedatanode10.5.3insertoperationtolinklist[eg10.8]createafunctioninsert()torealizeinsertinganewnodewhichdataisxaftertotheIstnodewhichispointedbyhead.analysis：comonsituationpre-inserted：after-inserted：standartconsideration：alongthepointerareaofthenodetofindtheistnode,finallyinsertnewnodeaftertheistnodebylinklistheadpointerhead1325NULL44ps132head5NULLSpecialsituation：1、nulllistpre=inserted：head=NULLafter-inserted：2、i=0pre-inserted：after-inserted：3、iout-of-range（i>thenumberofnode）disposingmanner：(1)error(2)inserttothetailhead4NULL4s132head5NULLhead4125NULL3structnode*insert(structnode*head,inti,intx){structnode*s,*p;s=(structnode*)malloc(LEN);s->num=x;if(head==NULL){head=s;s->next=NULL;}/*1、inserttothenulllinklist*/elseif(i==0)/*non-nulllinklist*/{s->next=head;head=s;}/*2、newnodeasnewheadnodeoflinklist*/else{p=head;/*lookuptheistnode(pointedbyp)*/for(;p!=NULL&&i>1;p=p->next,i--);if(p==NULL)/*3、errorout-of-range*/printf("Outoftherange,can'tinsert!\n");else/*4、commonsituation：ppointtotheistnode*/{s->next=p->next;p->next=s;}}return(head);}main(){structnode*head;inti,x;printf("inputdatatocreatlinklist(endby<=0):\n");head=creat();printf("thedataoflinklist:\n");print(head);printf("insert:i,x=");scanf("%d%d",&i,&x);insert(head,i,x);printf("thedataoflinklistafterinserted:\n");print(head);}10.5.4thedeleteoperationtolinklist[eg10.8]designafunctiondelete()，todeletethenodewhosedataisxinthelinklist。Commonsituation：Pre-deleted：After-deleted：q=head;p=q->next;/*lookupthenodewhosevalueisx*/for(;p->num!=x&&p!=NULL;q=p,p=p->next);if(p!=NULL)/*iffindit,ppointstothex,qpointstotheearlierone*/{q->next=p->next;free(p);}132head5NULLhead1325NULL4qpespescial：1、NULLlisthead=NULLerrorinformation2、deletetheheadnodepre-deleted：after-deleted：3、nosuchnodeerrorinformationhead4125NULL3head125NULL3structnode*delete_list(structnode*head,intx){structnode*p,*q;if(head==NULL)/*1、blanklist*/printf("Error!Thelistisempty.\n");elseif(head->num==x)/*2、deletethefirstnode*/head=head->next;else{q=head;p=q->next;for(;p->num!=x&&p!=NULL;q=p,p=p->next);if(p==NULL)/*3、notexist*/printf("Error!Thenumbeisnotexsist.\n");else{q->next=p->next;free(p);}/*deleteunheadednode*/}return(head);}10.5.5colligatedexample：menuprogramdesigning/*=======sortedlink_listoperater=======*//*DesignedbySunQiaoping*/#include"stdio.h";#defineNULL0#defineLENsizeof(structnode)structnode{intnum;structnode*next;};charmenu(void);voidprint(structnode*head);structnode*insert_sortedlist(structnode*head,intx);structnode*creat_sortedlist(void);structnode*delete_list(structnode*head,intx);main(){structnode*head=NULL;inti,x,flag=1;charch;do{ch=menu();clrscr();switch(ch){case'1':head=creat_sortedlist();break;case'2':printf("inputanumbertoinsert.x=");scanf("%d",&x);head=insert_sortedlist(head,x);break;case'3':printf("inputanumbertodelete.x=");scanf("%d",&x);head=delete_list(head,x);break;case'4':print(head);break;case'0':flag=0;}}while(flag==1);}/*========menu========*/charmenu(void){charch;clrscr();printf("MENU\n");/*puts()*/printf("==================\n");printf("1.creat\n");printf("2.insert\n");printf("3.delete\n");printf("4.print\n");printf("0.exit\n");printf("==================\n");printf("Inputyourchoice(0,1,2,3,4):");ch=getchar();return(ch);}/*========insert========*/structnode*insert_sortedlist(structnode*head,intx){structnode*s,*p,*q;s=(structnode*)malloc(LEN);s->num=x;if(head==NULL)/*inserttoablanklist*/{head=s;s->next=NULL;}elseif(x<=head->num)/*inserttoheadoflist*/{s->next=head;head=s;}else{q=head;p=q->next;/*lookuptheplacetoinsert*/for(;p!=NULL&&x>p->num;q=p,p=p->next);s->next=p;/*insertafterqandaheadofp*/q->next=s;}return(head);}Pre-inserted：After-inserted：head1368NULL44qs136head8NULLp/*========creat========*/structnode*creat_sortedlist(void){structnode*head;intx;printf("inputdatatocreatlinklist(endby<=0):\n");head=NULL;while(1){scanf("%d",&x);if(x<=0)break;head=insert_sortedlist(head,x);}return(head);}10.6introductiontounionandenum10.6.1union1．conceptionseveralvariablesofdifferenttypeoccupythesamesegmentofstorage.2．Definitionofunioncommonsituation：unionu_name{memberlist}；eg.uniondata{inti;charch;floatf;};Sameasdefinitionofstructuretype3．DefinitionofSharingvariables(1)indirectdefinitioneg：uniondataun1,un2,un3；(2)directdefiniton──definitevariableswhendefinitingtypeeg.union[data]{inti;charch;floatf;}un1,un2,un3;4．Thestoragelengthoccupiedbysharingvariables：thelengthoflongestmember5．Citingtosharingvariables──citingonebyone例如：un1.i、un1.ch、un1.f5．characteristic(1)Systemusestheoverlayingtechonologytorealizememorysharingofthesharingvariables’members,soanytimethereisonlyonemembervaluetostoreandbetake.eg，ifun1.i=1,un1.ch=‘c’,un1.f=3.14，un1.fisthevalidmember.(2)TheaddressofSharingvariableisthesameasthatofeverymember.eg，＆un1＝＆un1.i＝＆un1.ch＝＆un1.f(3)Cannotinitializesharingvariable(note:structurevariableispermitted)；norusingsharingvariableasfunctionparameter，neithernorreturningasharingdatabyfunction,butit’spermittedtouseapointerpointedtosharingvariable.(4)Sahringtypecanbeusedinstructuredefinition,thereverseisok!10.6.2enumeration1．Enumerationdefinitionenumweekdays{Sun,Mon,Tue,Wed,Thu,Fri,Sat}；enum_nameenum_element/enum_cv2．Enumeratedvariabledefinition(1)indirectdefinitionenumweekdaysworkday;(2)directdefinitionenum[weekdays]{Sun,Mon,Tue,Wed,Thu,Fri,Sat}workday;3．demonstration(1)uesedforlimiteddata.eg：1week7days,1years12months，5colors。(2)picktheelementupinlistasenumeration,whichisexplainedbyprogram.eg，notbecausewriteas“sun”,thatstandsfor“Sunday”.actually,enumelementcanbestandedbyanyname.(3)Enumelementislimitedasliteral──startby0socomparationisvalid.Comparationrules：thebiggerthenumberis,thebiggeritis.eg，inlastinstance,Sun=0、Mon=1、……、Sat=6，soMon>Sun、Satisthebiggest。(4)enum_elementischangable.whiledefiniting,itisspecifiedbyprogram.eg，definiteenumweekdays{Sun=7,Mon＝1,Tue,Wed,Thu,Fri,Sat}；soSun=7，Mon=１，beginwithTue=2，increaseby1。10.7TypedefCprovidesafacilitycalledtypedefforcreatingnewdatatypenames.Forexample,thedeclarationtypedeffloatREAL;/*creatnewdatatypenamerealforfloat*/REALx,y;/*definitethetypeofx,yasreal*//*itmeansthetypeofxandyisfloat*/[eg10.10]definitethealiasofstructurestructdateasDATE。structdate{intyear,month,day;};typedefstructdateDATE;DATAt,*p;equalto：typedefstructdate{intyear,month,day;}DATE;DATAt,*p;demonstration：1、todefiniteanaliastoaexistvariableusingtypedefwon’tcreatanewtype.2、differencebetweentypedefand#define：(1)typedefisdisposingwhencompiling；(2)#defineisdispoingwhenpreprocessing，asacounterpart