C/C++中结构体(struct)知识点强化

本文为【C/C++中结构体(struct)知识点强化】的汉字拼音对照版显示拼音

在zai上shang一yi个ge教jiao程cheng中zhong我wo们men已yi经jing简jian单dan的de阐chan述shu了le什shen么me是shi结jie构gou体ti了le，为wei了le进jin一yi部bu的de学xue习xi结jie构gou体ti这zhe一yi重chong要yao的de知zhi识shi点dian，我wo们men今jin天tian来lai学xue习xi一yi下xia链lian表biao结jie构gou。 结jie构gou体ti可ke以yi看kan做zuo是shi一yi种zhong自zi定ding义yi的de数shu据ju类lei型xing，它ta还huan有you一yi个ge很hen重chong要yao的de特te性xing，就jiu是shi结jie构gou体ti可ke以yi相xiang互hu嵌qian套tao使shi用yong，但dan也ye是shi有you条tiao件jian的de，结jie构gou体ti可ke以yi包bao含han结jie构gou体ti指zhi针zhen，但dan绝jue对dui不bu能neng在zai结jie构gou体ti中zhong包bao含han结jie构gou体ti变bian量liang。

strUCt test

{

char name[10];

float socre;

test *next;

};//这zhe样yang是shi正zheng确que的de!

struct test

{

char name[10];

float socre;

test next;

};//这zhe样yang是shi错cuo误wu的de!

利li用yong结jie构gou体ti的de这zhe点dian非fei凡fan特te性xing，我wo们men就jiu可ke以yi自zi己ji生sheng成cheng一yi个ge环huan环huan相xiang套tao的de一yi种zhong射she线xian结jie构gou，一yi个ge指zhi向xiang另ling一yi个ge。

链lian表biao的de学xue习xi不bu像xiang想xiang象xiang的de那na么me那na么me轻qing易yi，很hen多duo人ren学xue习xi到dao这zhe里li的de时shi候hou都dou会hui碰peng到dao困kun难nan，很hen多duo人ren也ye因yin此ci而er放fang弃qi了le学xue习xi，在zai这zhe里li我wo说shuo,一yi定ding不bu能neng放fang弃qi，对dui应ying它ta的de学xue习xi我wo们men要yao进jin行xing分fen解jie式shi学xue习xi，方fang法fa很hen重chong要yao，理li解jie需xu要yao时shi间jian，不bu必bi要yao把ba自zi己ji逼bi迫po的de那na么me紧jin，学xue习xi前qian你ni也ye得de做zuo一yi些xie最zui基ji本ben的de预yu备bei工gong作zuo，你ni必bi须xu具ju备bei对dui堆dui内nei存cun的de基ji本ben知zhi识shi的de了le解jie，还huan有you就jiu是shi对dui结jie构gou体ti的de基ji本ben熟shu悉xi，有you了le这zhe两liang个ge重chong要yao的de条tiao件jian，再zai进jin行xing分fen解jie式shi学xue习xi就jiu可ke以yi比bi较jiao轻qing松song的de把ba握wo这zhe一yi节jie内nei容rong的de难nan点dian。

下xia面mian我wo们men给gei出chu一yi个ge完wan整zheng的de创chuang建jian链lian表biao的de程cheng序xu，不bu管guan看kan的de懂dong看kan不bu懂dong希xi望wang读du者zhe先xian认ren真zhen看kan一yi下xia，想xiang一yi想xiang，看kan不bu懂dong没mei有you关guan系xi，因yin为wei我wo下xia面mian会hui有you分fen解jie式shi的de教jiao程cheng，但dan之zhi前qian的de基ji本ben思si考kao一yi定ding要yao做zuo，要yao不bu即ji使shi我wo分fen解jie了le你ni也ye是shi无wu从cong理li解jie的de。

代dai码ma如ru下xia，我wo在zai重chong要yao部bu分fen做zuo了le注zhu解jie：

#include <iostream>

using namespace std;

struct test

{

char name[10];

float socre;

test *next;

};

test *head;//创chuang建jian一yi个ge全quan局ju的de引yin导dao进jin入ru链lian表biao的de指zhi针zhen

test *create()

{

test *ls;//节jie点dian指zhi针zhen

test *le;//链lian尾yi指zhi针zhen

ls = new test;//把bals指zhi向xiang动dong态tai开kai辟pi的de堆dui内nei存cun地di址zhi

cin>>ls->name>>ls->socre;

head=NULL;//进jin入ru的de时shi候hou先xian不bu设she置zhihead指zhi针zhen指zhi向xiang任ren何he地di址zhi,因yin为wei不bu知zhi道dao是shi否fou一yi上shang来lai就jiu输shu入runull跳tiao出chu程cheng序xu

le=ls;//把ba链lian尾yi指zhi针zhen设she置zhi成cheng刚gang刚gang动dong态tai开kai辟pi的de堆dui内nei存cun地di址zhi,用yong于yu等deng下xia设she置zhile->next,也ye就jiu是shi下xia一yi个ge节jie点dian的de位wei置zhi

while(strcmp(ls->name,"null")!=0)//创chuang建jian循xun环huan条tiao件jian为weils->name的de值zhi不bu是shinull,用yong于yu循xun环huan添tian加jia节jie点dian

{

if(head==NULL)//判pan定ding是shi否fou是shi第di一yi次ci进jin入ru循xun环huan

{

head=ls;//假jia如ru是shi第di一yi次ci进jin入ru循xun环huan,那na么me把ba引yin导dao进jin入ru链lian表biao的de指zhi针zhen指zhi向xiang第di一yi次ci动dong态tai开kai辟pi的de堆dui内nei存cun地di址zhi

}

else

{

le->next=ls;//假jia如ru不bu是shi第di一yi次ci进jin入ru那na么me就jiu把ba上shang一yi次ci的de链lian尾yi指zhi针zhen的dele->next指zhi向xiang上shang一yi次ci循xun环huan结jie束shu前qian动dong态tai创chuang建jian的de堆dui内nei存cun地di址zhi

}

le=ls;//设she置zhi链lian尾yi指zhi针zhen为wei当dang前qian循xun环huan中zhong的de节jie点dian指zhi针zhen,用yong于yu下xia一yi次ci进jin入ru循xun环huan的de时shi候hou把ba上shang一yi次ci的de节jie点dian的denext指zhi向xiang上shang一yi次ci循xun环huan结jie束shu前qian动dong态tai创chuang建jian的de堆dui内nei存cun地di址zhi

ls=new test;//为wei下xia一yi个ge节jie点dian在zai堆dui内nei存cun中zhong动dong态tai开kai辟pi空kong间jian

cin>>ls->name>>ls->socre;

}

le->next=NULL;//把ba链lian尾yi指zhi针zhen的denext设she置zhi为wei空kong,因yin为wei不bu管guan如ru何he循xun环huan总zong是shi要yao结jie束shu的de,设she置zhi为wei空kong才cai能neng够gou在zai循xun环huan显xian链lian表biao的de时shi候hou不bu至zhi于yu死si循xun环huan

delete ls;//当dang结jie束shu的de时shi候hou最zui后hou一yi个ge动dong态tai开kai辟pi的de内nei存cun是shi无wu效xiao的de,所suo以yi必bi须xu清qing除chu掉diao

return head;//返fan回hui链lian首shou指zhi针zhen

}

void showl(test *head)

{

cout<<"链lian首shou指zhi针zhen:"<<head<<endl;

while(head)//以yi内nei存cun指zhi向xiang为weinull为wei条tiao件jian循xun环huan显xian示shi先xian前qian输shu入ru的de内nei容rong

{

cout<<head->name<<""<<head->socre<<endl;

head=head->next;

}

}

void main()

{

showl(create());

cin.get();

cin.get();

}

上shang面mian的de代dai码ma我wo们men是shi要yao达da到dao一yi个ge目mu的de：就jiu是shi要yao存cun储chu你ni输shu入ru的de人ren名ming和he他ta们men的de得de分fen，并bing且qie以yi链lian状zhuang结jie构gou把ba它ta们men组zu合he成cheng一yi个ge链lian状zhuang结jie构gou。

程cheng序xu种zhong有you两liang个ge组zu成cheng部bu分fen

test *create() 和he

void showl(test *head)

这zhe两liang个ge函han数shu，create是shi用yong来lai创chuang建jian链lian表biao的de ，showl是shi用yong来lai显xian示shi链lian表biao的de。

create函han数shu的de返fan回hui类lei型xing是shi一yi个ge结jie构gou体ti指zhi针zhen，在zai程cheng序xu调tiao用yong的de时shi候hou我wo们men用yong了leshowl(create());，而er不bu用yong引yin用yong的de目mu的de原yuan因yin是shi引yin导dao指zhi针zhen是shi一yi个ge全quan局ju指zhi针zhen变bian量liang，我wo们men不bu能neng在zaishowl()内nei改gai变bian它ta，因yin为weishowl()函han数shu内nei有you一yi个ge移yi动dong操cao作zuohead=head->next;，假jia如ru是shi引yin用yong的de话hua我wo们men就jiu破po坏huai了lehead指zhi针zhen的de位wei置zhi，以yi至zhi于yu我wo们men再zai也ye无wu法fa找zhao会hui首shou地di址zhi的de位wei置zhi了le。

下xia面mian我wo们men来lai分fen解jie整zheng个ge程cheng序xu，以yi一yi个ge初chu学xue者zhe的de思si想xiang来lai思si考kao整zheng个ge程cheng序xu，由you浅qian入ru深shen的de逐zhu步bu解jie释shi。

首shou先xian，我wo们men写xie这zhe个ge程cheng序xu，要yao考kao虑lv到dao由you于yu是shi一yi个ge链lian表biao结jie构gou，我wo们men不bu可ke能neng知zhi道dao它ta的de大da小xiao到dao底di是shi多duo大da，这zhe个ge问wen题ti我wo们men可ke以yi用yong动dong态tai开kai辟pi堆dui内nei存cun来lai解jie决jue，因yin为wei堆dui内nei存cun在zai程cheng序xu结jie束shu前qian始shi终zhong是shi有you效xiao的de，不bu受shou函han数shu栈zhan空kong间jian生sheng命ming期qi的de限xian制zhi，但dan要yao注zhu重chong的de是shi我wo们men必bi须xu有you一yi个ge指zhi针zhen变bian量liang来lai存cun储chu这zhe一yi链lian状zhuang结jie构gou的de进jin入ru地di址zhi，而er在zai函han数shu内nei部bu来lai建jian立li这zhe一yi指zhi针zhen变bian量liang显xian然ran是shi不bu合he适shi的de，因yin为wei函han数shu一yi旦dan退tui出chu，这zhe个ge指zhi针zhen变bian量liang也ye随sui之zhi失shi效xiao，所suo以yi我wo们men在zai程cheng序xu的de开kai始shi声sheng明ming了le一yi个ge全quan局ju指zhi针zhen变bian量liang。

test *head;//创chuang建jian一yi个ge全quan局ju的de引yin导dao进jin入ru链lian表biao的de指zhi针zhen

好hao解jie决jue了le这zhe两liang个ge问wen题ti，我wo们men接jie下xia去qu思si考kao

有you输shu入ru就jiu必bi然ran有you输shu出chu，由you于yu输shu出chu函han数shu和he输shu入ru函han数shu是shi相xiang对dui独du立li的de，为wei了le不bu断duan测ce试shi程cheng序xu的de正zheng确que性xing好hao调tiao试shi我wo们men先xian写xie好hao输shu出chu函han数shu和hemain函han数shu捏nie的de调tiao用yong，创chuang建jian函han数shu我wo们men先xian约yue定ding好hao名ming为weicreate。

我wo们men先xian写xie出chu如ru下xia的de代dai码ma：

#include <iostream>

using namespace std;

struct test

{

char name[10];

float socre;

test *next;

};

test *head;//创chuang建jian一yi个ge全quan局ju的de引yin导dao进jin入ru链lian表biao的de指zhi针zhen

test *create()

{

return head;//返fan回hui链lian首shou指zhi针zhen

}

void showl(test *head)

{

cout<<"链lian首shou指zhi针zhen:"<<head<<endl;

while(head)//以yi内nei存cun指zhi向xiang为weinull为wei条tiao件jian循xun环huan显xian示shi先xian前qian输shu入ru的de内nei容rong

{

cout<<head->name<<""<<head->socre<<endl;

head=head->next;

}

}

void main()

{

showl(create());

cin.get();

cin.get();

}

程cheng序xu写xie到dao这zhe里li，基ji本ben形xing态tai已yi经jing出chu来lai，输shu入ru和he调tiao用yong我wo们men已yi经jing有you了le。

下xia面mian我wo们men来lai解jie决jue输shu入ru问wen题ti，链lian表biao的de实shi现xian我wo们men是shi通tong过guo循xun环huan输shu入ru来lai实shi现xian的de，既ji然ran是shi循xun环huan我wo们men就jiu一yi定ding得de考kao虑lv终zhong止zhi循xun环huan的de条tiao件jian，避bi免mian死si循xun环huan和he无wu效xiao循xun环huan的de发fa生sheng。

在zaicreate()函han数shu内nei部bu我wo们men先xian写xie成cheng这zhe样yang：

test *create()

{

test *ls;//节jie点dian指zhi针zhen

test *le;//链lian尾yi指zhi针zhen

ls = new test;//把bals指zhi向xiang动dong态tai开kai辟pi的de堆dui内nei存cun地di址zhi

cin>>ls->name>>ls->socre;

head=NULL;//进jin入ru的de时shi候hou先xian不bu设she置zhihead指zhi针zhen指zhi向xiang任ren何he地di址zhi,因yin为wei不bu知zhi道dao是shi否fou一yi上shang来lai就jiu输shu入runull跳tiao出chu程cheng序xu

le=ls;//把ba链lian尾yi指zhi针zhen设she置zhi成cheng刚gang刚gang动dong态tai开kai辟pi的de堆dui内nei存cun地di址zhi,用yong于yu等deng下xia设she置zhile->next,也ye就jiu是shi下xia一yi个ge节jie点dian的de位wei置zhi

le->next=NULL;//把ba链lian尾yi指zhi针zhen的denext设she置zhi为wei空kong,因yin为wei不bu管guan如ru何he循xun环huan总zong是shi要yao结jie束shu的de,设she置zhi为wei空kong才cai能neng够gou在zai循xun环huan显xian链lian表biao的de时shi候hou不bu至zhi于yu死si循xun环huan

delete ls;//当dang结jie束shu的de时shi候hou最zui后hou一yi个ge动dong态tai开kai辟pi的de内nei存cun是shi无wu效xiao的de,所suo以yi必bi须xu清qing除chu掉diao

return head;//返fan回hui链lian首shou指zhi针zhen

}

在zai循xun环huan创chuang建jian之zhi前qian我wo们men必bi须xu考kao虑lv一yi个ge都dou不bu输shu入ru的de情qing况kuang。

程cheng序xu一yi单dan进jin入rucreate函han数shu我wo们men首shou先xian必bi然ran要yao创chuang建jian一yi个ge节jie点dian，我wo们men先xian创chuang建jian一yi个ge节jie点dian指zhi针zhen，后hou把ba者zhe个ge节jie点dian指zhi针zhen指zhi向xiang到dao动dong态tai开kai辟pi的detest类lei型xing的de动dong态tai内nei存cun地di址zhi位wei置zhi上shang。

所suo以yi我wo们men有you了le

test *ls;

ls = new test;

程cheng序xu既ji然ran是shi循xun环huan输shu入ru，而er结jie构gou成cheng员yuantest *next又you是shi用yong来lai存cun储chu下xia一yi个ge接jie点dian的de内nei存cun地di址zhi的de，每mei次ci循xun环huan我wo们men又you要yao动dong态tai创chuang建jian一yi个ge新xin的de内nei存cun空kong间jian，所suo以yi我wo们men必bi须xu要yao有you一yi个ge指zhi针zhen来lai存cun储chu上shang一yi次ci循xun环huan动dong态tai开kai辟pi的de内nei存cun地di址zhi，于yu是shi就jiu有you了le

test *le;

接jie下xia来lai在zai进jin入ru循xun环huan前qian我wo们men要yao创chuang建jian链lian表biao的de第di一yi个ge节jie点dian，第di一yi个ge节jie点dian必bi然ran是shi在zai循xun环huan外wai创chuang建jian，于yu是shi就jiu有you了le

cin>>ls->name>>ls->socre;

程cheng序xu执zhi行xing者zhe的de情qing况kuang是shi位wei置zhi的de，所suo以yi我wo们men必bi然ran要yao考kao虑lv，一yi上shang来lai就jiu不bu想xiang继ji续xu运yun行xing程cheng序xu的de情qing况kuang，所suo以yi我wo们men一yi开kai始shi先xian把bahead引yin导dao指zhi针zhen设she置zhi为wei不bu指zhi向xiang任ren何he地di址zhi也ye就jiu是shi

head=NULL;

为wei了le符fu合hele也ye就jiu是shi链lian尾yi指zhi针zhen的de设she计ji思si路lu，我wo们men在zai循xun环huan前qian一yi定ding要yao保bao存cun刚gang刚gang动dong态tai开kai辟pi的de内nei存cun地di址zhi，好hao在zai下xia一yi次ci循xun环huan的de时shi候hou设she置zhi上shang一yi个ge节jie点dian中zhong的denext成cheng员yuan指zhi向xiang，于yu是shi我wo们men便bian有you了le：

le=ls;

为wei了le实shi现xian循xun环huan输shu入ru我wo们men又you了le下xia面mian的de代dai码ma：

while(strcmp(ls->name,"null")!=0)

{

if(head==NULL)

{

head=ls;

}

else

{

le->next=ls;

}

le=ls;

ls=new test;

cin>>ls->name>>ls->socre;

}

程cheng序xu是shi循xun环huan必bi然ran要yao有you终zhong止zhi循xun环huan的de条tiao件jian，所suo以yi我wo们men的de循xun环huan条tiao件jian是shi：

while(strcmp(ls->name,"null")!=0)

输shu入ru的de名ming字zi是shinull的de时shi候hou就jiu停ting止zhi循xun环huan。

为wei了le保bao证zheng第di一yi次ci进jin入ru循xun环huan，也ye就jiu是shi在zai循xun环huan内nei预yu备bei创chuang建jian第di二er个ge节jie点dian前qian，设she置zhi引yin导dao指zhi针zhen的de指zhi向xiang我wo们men有you了le如ru下xia的de判pan定ding代dai码ma：

if(head==NULL)

{

head=ls;

}

else

{

le->next=ls;

}

代dai码ma中zhong的deelse条tiao件jian是shi为wei了le设she置zhi前qian一yi个ge节jie点diannext指zhi向xiang而er写xie的de,这zhe点dian我wo们men记ji住zhu先xian看kan下xia面mian的de代dai码ma,稍shao后hou大da家jia回hui过guo头tou想xiang就jiu明ming白bai了le

le=ls;

ls=new test;

cin>>ls->name>>ls->socre;

le=ls;这zhe么me写xie就jiu是shi为wei了le保bao存cun上shang一yi次ci循xun环huan指zhi针zhen的de位wei置zhi而er设she的de,正zheng是shi为wei了le上shang面mian的deelse代dai码ma而er做zuo的de预yu先xian保bao留liu

ls=new test;

cin>>ls->name>>ls->socre;

这zhe两liang行xing代dai码ma的de意yi思si就jiu是shi继ji续xu开kai辟pi下xia一yi个ge节jie点dian空kong间jian,和he输shu入ru节jie点dian内nei容rong!

循xun环huan一yi旦dan结jie束shu也ye就jiu结jie束shu了le程cheng序xu,为wei了le保bao持chi程cheng序xu不bu出chu错cuo,也ye就jiu是shi最zui后hou一yi个ge节jie点dian的denext成cheng员yuan指zhi向xiang为wei空kong我wo们men有you了le下xia面mian的de代dai码ma

le->next=NULL;

程cheng序xu的de思si路lu始shi终zhong是shi以yi先xian开kai辟pi后hou判pan定ding为wei思si路lu的de,所suo以yi到dao最zui后hou一yi个ge不bu成cheng立li的de时shi候hou总zong会hui有you一yi个ge多duo开kai辟pi的de内nei存cun空kong间jian,为wei了le删shan除chu掉diao它ta,我wo们men有you了le下xia面mian的de代dai码ma

delete ls;

程cheng序xu到dao最zui后hou由you于yu返fan回huihead指zhi针zhen

return head;

显xian示shi链lian表biao的de函han数shu没mei有you什shen么me太tai多duo非fei凡fan的de也ye只zhi需xu要yao注zhu重chong下xia面mian这zhe样yang就jiu可ke以yi了le！