浙江大学C颜晖原版C9ppt课件

第九章结构,结构结构数组结构指针链表位运算自定义类型,学号,姓名,性别,出生地,出生年,出生月,出生日,数学,物理,程序设计,结构：同一个数据项的若干成分构成的一个整体。例如：学生档案，每个学生有学号、姓名、性别、出生地、出生年月、学业成绩等。,9.1结构,9.1.1结构的定义structstudentlongintnum;charname20;floatscore;定义一个结构类型：structstudent,9.1.2结构变量的定义,1、先定义结构类型，再定义变量structstudentlongintnum;charname20;floatscore;structstudentstu1,stu2;,2、定义结构类型的同时定义变量structstudentlongintnum;charname20;floatscore;stu1,stu2;,3、不指定类型名，只定义变量structlongintnum;charname20;floatscore;stu1,stu2;,9.1.3结构变量的初始化,只有全局变量或静态变量才能初始化。staticstructstudentstu2=200012,“Li”,94;,structstudentlongnum;charname20;floatscore;stu1=200011,Zhang,85;,9.1.4结构变量的使用,1、结构类型变量的整体引用(1)不能整体输入输出，但相同类型的变量可以互相赋值printf(%ld%s%f,stu1);非法stu2=stu1;合法(2)可以引用结构体变量的地址printf(%x,输出stu1的首地址,2、结构变量中分量的引用structstudentlongintnum;charname20;floatscore;stu1,stu2;,(1)结构变量.分量stu1.num=9901;printf(%s,);,(2)结构变量中的分量可以依据它的类型进行各种运算x=stu1.score;strcpy(,“Wang”);(3)可以引用结构变量中的分量的地址scanf(%ld,9.2结构数组,一个结构变量只能存放一个学生的资料。若班上有20个学生，需要用结构数组。即，数组中的每个元素都是结构类型。9.2.1定义structstudentlongintnum;charname20;floatscore;stu20;,9.2.2初始化structstudentlongintnum;charname20;floatscore;stu20=200011,”Zhang”,85,200012,”Li”,90;,9.2.3引用structstudentlongintnum;charname20;floatscore;stu20；stu0.score,程序举例,例1、输入某班30位学生的姓名及数学、英语成绩，计算并输出每位学生的平均分。structstudentcharname10;intmath,eng;floataver;,voidmain()structstudents30;inti;for(i=0;i30;i+)scanf(%s%d%d,,输入某班30位学生的姓名及数学、英语成绩，计算并输出每门课程的平均分。voidmain()structstudents30;inti;floataver_m=0,aver_e=0;,例2,for(i=0;inum=200011;ptr-score=85;strcpy(ptr-name,”Zhang”);当ptr=intm;intd;,structstudentlongintnum;charname20;structdaybirthday;floatscore;,structdayinty;intm;intd;structstudentlongintnum;charname20;structdaybirthday;floatscore;stu1,stu2;,或：structstudentlongintnum;charname20;structinty,m,d;birthday;floatscore;stu1,stu2;,structstudentlongintnum;charname20;structinty,m,d;birthday;floatscore;stu1=9901,“Zhao”,1980,10,30,80,stu2;stu2.birthday.y=1979;stu2.birthday.y=1;stu2.birthday.y=20;,9.4.2单向链表,structstudentlongintnum;floatscore;structstudent*next;结构的递归定义,1、动态内存分配函数,(1)void*malloc(unsignedsize)功能：在内存的动态存贮区中分配一块长度为size的连续空间。返回值：指针，存放被分配内存的起始地址。若未申请到空间，则返回NULL(0)。void*：指向任何类型的数据，在使用时，要进行强制类型转换。例如：(int*)malloc(sizeof(int)(structstudent*)malloc(sizeof(structstudent),(2)voidfree(void*ptr)功能：释放由malloc()申请的动态内存空间，ptr存放该空间的首地址。返回值：无。p=(structstudent*)malloc(sizeof(structstudent);free(p);,2、建立链表,编写一个函数，要求用单向链表建立学生档案，从键盘输入数据，如果学号为0，输入结束，并返回链表的头指针。structstudentlongintnum;floatscore;structstudent*next;；structstudent*head,*tail,*p;head=tail=NULL;,structstudent*head,*tail,*p;head=tail=NULL;size=sizeof(structstudent);p=(structstudent*)malloc(size);,p,head,tail,tail,head=tail=NULL;inputnum,scorewhilenum!=0p=(structstudent*)malloc(sizeof(size)p-num=num,p-score=score,p-next=NULLyhead=NULLnhead=ptail-next=ptail=pinputnum,score,#includestdio.hstructstudentintnum;floatscore;structstudent*next;structstudent*creat();main()structstudent*head;head=creat();,structstudent*creat()structstudent*head,*tail,*p;floatscore;intnum,size=sizeof(structstudent);head=tail=NULL;scanf(%d%f,3、遍历链表,ptr-numptr-score,for(ptr=head;ptr!=NULL;ptr=ptr-next)printf(“%ld,%f”,ptr-num,ptr-score);,ptr=ptr-next,#includestdio.hstructstudentintnum;floatscore;structstudent*next;structstudent*creat();voidprint(structstudent*head)main()structstudent*head;head=creat();print(head);,voidprint(structstudent*head)structstudent*ptr;if(head=NULL)printf(nNolistn);return;printf(nlistn);for(ptr=head;ptr;ptr=ptr-next)printf(%d%fn,ptr-num,ptr-score);,4、对链表的删除操作,ptr2=ptr1-nextptr1-next=ptr2-next,free(ptr2)ptr2=ptr1-next,4、对链表的插入操作,s-next=ptr-nextptr-next=s先连后断,9.5位运算,9.5.1位运算符1、位逻辑运算符按位取反(与!