C语言例题第八章

第八章structscore{intno;charname[20];intenglish;intmath;intcomputer;intclang;}；1、先定义结构类型，再定义结构变量。如：structscore{intno;charname[20];intenglish;intcomputer;intclang;};structscorestu1,stu2;定义了两个变量stu1和stu2为score结构类型。2、在定义结构类型的同时定义结构变量。例如：structscore{intno;charname[20];intenglish;intmath;intcomputer;intclang;}stu1,stu2;3.也可以直接定义结构变量。例如：struct{intno;charname[20];intenglish;intmath;intcomputer;

intclang;}stu1,stu2;例如，下面是一个新的结构类型的定义：structdate{intmonth;intday;intyear;}struct{intnum;charname[20];charsex;structdatebirthday;floatscore;}stu1,stu2;【例8.1】从键盘上输入一个人的姓名、年龄、性别和身高，然后将它们打印出来。#include"stdio.h"main(){structperson{charname[20];intage;intsex;floatheight;}person1;printf("pleaseinputname:\n");scanf("%s",);printf("pleaseinputage:\n");scanf("%d",&person1.age);printf("pleaseinputsex(0formaleand1forfemale):\n");scanf("%d",&person1.sex);printf("pleaseinputheight:\n");scanf("%f",&person1.height);printf("theresultis:\n");printf("name:%s\nage:%d\n",,person1.age);if(person1.sex==0)printf("sex:male\n");if(person1.sex==1)printf("sex:female\n");printf("height:%.2fm\n",person1.height);}

【例8.2】给结构变量赋值并输出其值。#include"stdio.h"main(){structstu{intnum;char*name;charsex;floatscore;}stu1,stu2;stu1.num=101;="张三";printf("请输入性别和成绩：\n");scanf("%c%f",&stu1.sex,&stu.score);stu2=stu1;printf("学号=%d\n姓名=%s\n",stu2.num,);printf("性别=%c\n成绩=%f\n",stu2.sex,stu2.score);}【例8.3】外部结构变量初始化。#include"stdio.h"structstudent/*定义外部结构变量{intnum;*/char*name;charsex;floatscore;}stu2,stu1={101,"张三",'M',90};main(){stu2=stu1;printf("学号=%d\n姓名=%s\n",stu2.num,);printf("性别=%c\n成绩=%f\n",stu2.sex,stu2.score);}【例8.4】静态结构变量初始化。#include"stdio.h"main(){staticstructstudent/*定义静态结构变量*/{intnum;char*name;charsex;floatscore;}stu2,stu1={101,"张三",'M',90};stu2=stu1;

printf("学号=%d\n姓名=%s\n",stu2.num,);printf("性别=%c\n成绩=%f\n",stu2.sex,stu2.score);}structstu{intnum;char*name;charsex;floatscore;}boy[5]={{101,"Liping","M",45},{102,"Zhangping","M",62.5},{103,"Hefang","F",92.5},{104,"Chengling","F",87},{105,"Wangming","M",58};}【例8.5】计算学生的平均成绩和不及格的人数。#include"stdio.h"structstu{intnum;char*name;charsex;floatscore;}boy[5]={{101,"Liping",'M',45},{102,"Zhangping",'M',62.5},{103,"Hefang",'F',92.5},{104,"Chengling",'F',87},{105,"Wangming",'M',58},};main(){inti,c=0;floatave,s=0;for(i=0;i<5;i++){s+=boy[i].score;if(boy[i].score<60)c+=1;}printf("s=%f\n",s);ave=s/5;printf("average=%f\ncount=%d\n",ave,c);

}【例8.6】通讯录#include"stdio.h"#defineNUM3structmem{charname[20];charphone[10];};main(){structmemman[NUM];inti;for(i=0;i<NUM;i++){printf("inputname:\n");gets(man[i].name);printf("inputphone:\n");gets(man[i].phone);}printf("name\t\t\tphone\n\n");for(i=0;i<NUM;i++)printf("%s\t\t\t%s\n",man[i].name,man[i].phone);}此外，结构数组的成员也可以是数组变量。例如：structa{intm[3][5];floatf;chars[20];}y[4];为了访问结构a中结构变量y[2]的这个变量,可写成：y[2].m[1][4]。6个优秀团员。下面编写一个程序来统计【例8.7】在某班中共有30个同学，要选出每一个候选人的得票数量。#include"stdio.h"#include"string.h"structperson{charname[20];intsum;};

main(){structpersoncandidate[6]={{"Zhang",0},{"Wang",0},{"Li",0},{"Zhao",0},{"Liu",0},{"Qian",0}};inti,j;chartname[20];for(i=0;i<30;i++){scanf("%s",tname);for(j=0;j<6;j++)if(strcmp(candidate[j].name,tname)==0)candidate[j].sum++;}printf("\n");for(j=0;j<6;j++)printf("%10s:%d\n",candidate[j].name,candidate[j].sum);}【例8.8】结构指针变量的使用方法举例。#include"stdio.h"structstu{intnum;char*name;charsex;floatscore;}boy1={102,"ZhangSan",'M',88},*pstu;main(){pstu=&boy1;printf("Number=%d\nName=%s\n",boy1.num,);printf("Sex=%c\nScore=%f\n\n",boy1.sex,boy1.score);printf("Number=%d\nName=%s\n",(*pstu).num,(*pstu).name);printf("Sex=%c\nScore=%f\n\n",(*pstu).sex,(*pstu).score);printf("Number=%d\nName=%s\n",pstu->num,pstu->name);printf("Sex=%c\nScore=%f\n\n",pstu->sex,pstu->score);}【例8.9】用指针变量输出结构数组。#include"stdio.h"structstu{intnum;char*name;charsex;floatscore;

}boy[5]={{101,"Zhouping",'M',45},{102,"Zhangping",'M',62.5},{103,"Lioufang",'F',92.5},{104,"Chengling",'F',87},{105,"Wangming",'M',58},};main(){structstu*ps;printf("No\tName\t\t\tSex\tScore\t\n");for(ps=boy;ps<boy+5;ps++)printf("%d\t%s\t\t%c\t%f\t\n",ps->num,ps->name,ps->sex,ps->score);}【例8.10】用结构指针变量作函数参数计算一组学生的平均成绩和不及格人数。#include"stdio.h"structstu{intnum;char*name;charsex;floatscore;}boy[5]={{101,"Liping",'M',45},{102,"Zhangping",'M',62.5},{103,"Hefang",'F',92.5},{104,"Chengling",'F',87},{105,"Wangming",'M',58},};main(){structstu*ps;voidave(structstu*ps);ps=boy;ave(ps);}voidave(structstu*ps){intc=0,i;floatave,s=0;for(i=0;i<5;i++,ps++){s+=ps->score;if(ps->score<60)c+=1;}printf("s=%f\n",s);ave=s/5;printf("average=%f\ncount=%d\n",ave,c);}

【例8.11】定义一个共用体类型，用于存储教师或学生的信息。编程输入相关信息并输出。#include"stdio.h"main(){struct{charname[10];intage;charjob;union{intclass;charoffice[10];}depa;}body[2];intn,i;for(i=0;i<2;i++){printf("inputname,age,jobanddepartment\n");scanf("%s%d%c",body[i].name,&body[i].age,&body[i].job);if(body[i].job=='s')scanf("%d",&body[i].depa.class);elsescanf("%s",body[i].depa.office);}printf("name\tagejobclass/office\n");for(i=0;i<2;i++)/*输出各成员项的值*/{if(body[i].job=='s')printf("%s\t%3d%3c%d\n",body[i].name,body[i].age,body[i].job,body[i].depa.class);elseprintf("%s\t%3d%3c%s\n",body[i].name,body[i].age,body[i].job,body[i].depa.office);}}【例8.12】枚举类型使用举例。#include"stdio.h"main(){enumbody{a,b,c,d}month[31],j;inti;j=a;for(i=1;i<=30;i++){month[i]=j;

j++;if(j>d)j=a;}for(i=1;i<=30;i++){switch(month[i]){casea:printf("%2d%c\t",i,'a');break;caseb:printf("%2d%c\t",i,'b');break;casec:printf("%2d%c\t",i,'c');break;cased:printf("%2d%c\t",i,'d');break;default:break;}}printf("\n");}8.4习题8-1选择题1.有定义如下：structsk{inta；floatb；}data,*p；如果p=&data；则对于结构变量data的成员a的正确引用是()。A．（*）.data.aB.(*p).aC．p->data.aD.p.data.a2.已知：structst{intn；structst*next；}；staticstructsta[3]={1,&a[1],3,&a[2],5,&a[0]},*p；2，则对p的赋值是()。printf("%d",++(p->next->n))；A.p=&a[0]；B.p=&a[1]；C.p=&a[2]；D.p=&a[3]；3.已知：如果下述语句的显示是structperson{charname[10]；intage；}class[10]={"LiMing",29,"ZhangHong",21,"WangFang",22}；下述表达式中，值为72的一个是____。A.class[0]->age+class[1]->age+class[2]->ageB.class[1].name[5]C.person[1].name[5]D.clase->name[5]4.已知：

struct{inti；charc；floata；}test；则sizeof(test)的值是。A.4B.5C.6D.75.已知：union{inti；charc；floata；}test；则sizeof(test)的值是A.4B.5C.6D.76.已知：()。unionu_type{inti；charch；floata；}temp；现在执行"temp.i=266；printf("%d",temp.ch)"的结果是()。A.266B.256C.10D.17.若有以下程序段：structdent{intn；int*m；}；inta=1,b=2,c=3；structdents[3]={{101,&a},{102,&b},{103,&c}}；structdent*p=s；则以下表达式中值为2的是()。A.(p++)->mB.*(p++)->mC.(*p).mD.*(++p)->m8.若有以下说明语句，则对结构变量structpupil{charname[20]；intsex；pup中sex域的正确引用是()。}pup,*p；p=&pup；A.p.pup.sexB.p->pup.sexC.(*p).pup.sexD.(*p).sex9.以下对结构变量stul中成员age的非法引用是()。structstudent{intage；intnum；

}stu1,*p；p=&stu1；A.stu1.ageB.student.ageC.p->ageD.(*p).age10.若有以下定义和语句：uniondata{inti；charc；floatf；}a；intn；则以下语句正确的是()。A.a=5；B.a={2,'a',1.2}；C.printf("%d\n",a)；D.n=a；11.已知：structsk{inta；intage；}date,*p；如果要使指针p指向data中的成员a，正确的赋值语句是()。A.p=(structsk*)&data.a；B.p=(structsk*)data.a；C.p=&data.a；D.*p=data.a；12.已知enumweek{sun,mon,tue,wed,thu,fri,sat}day；则正确的赋值语句是A.sun=0；B.san=day；C.sun=mon；D.day=sun；13.已知enumcolor{red,yellow=2,blue,white,black}ren；执行下述语句的输出结果是printf("%d",ren=white)；()。()A.0B.1C.3D.414.已知enumname{zhao=1,qian,sun,li}man；执行下述程序段后的输出是man=0；____。switch(man){case0:printf("People\n")；case1:printf("Man\n")；case2:printf("Woman\n")；default:printf("Error\n")；}A.PeopleB.ManC.WomanD.Error15.下述关于枚举类型名的定义中，正确的是____。A.enema={one,two,three}；B.enema{one=9,two=-1,three}；C.enema={"one","two","three"}；D.enema{"one","two","three"}；8-2程序填空1.下面程序的功能是输入学生的姓名和成绩，然后输出。#include<stdio.h>structstuinf{charname[20]；/*学生姓名intscore；/*学生成绩}stu,*p；*/*/

main(){p=&stu；printf("Entername:")；gets(①)；printf("Enterscore:")；scanf("%d"，②)；printf("Output:%s,%d\n"，③，④)；}2.下面程序的功能是按学生的姓名查询其成绩排名和平均成绩。查询时可连续进行，直到输入0时才结束。#include<stdio.h>#include<string.h>#defineNUM4structstudent{intrank；char*name；floatscore；}；①stu[]={3，"liming"，89.3，4，"zhanghua"，78.2，1，"anli"，95.1，2，"wangqi"，90.6}；•main(){charstr[10]；•inti；•do{printf("Enteraname")；•••scanf("%s"，str)；•••