C语言程序设计教程杨路明课后习题答案北京邮电大学出版社.pdf

file:/F|/khdaw/暑假/c语言习题/第1章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:17 1、算法描述主要是用两种基本方法：第一是自然语言描述，第二是使用专用工具进行算法描述 2、c语言程序的结构如下： 1、c语言程序由函数组成，每个程序必须具有一个main函数作为程序的主控函数。 2、“/*“与“*/“之间的内容构成c语言程序的注释部分。 3、用预处理命令#include可以包含有关文件的信息。 4、大小写字母在c语言中是有区别的。 5、除main函数和标准库函数以外，用户可以自己编写函数，程序一般由多个函数组成，这些函数制定实际 所需要做的工作。 例如： void main() int a,b,c,s; a=8;b=12;c=6; s=a+b*c; printf(“s=%dn“,s); 3、c语言的特点： 1、c语言具有结构语言的特点，程序之间很容易实现段的共享； 2、c语言的主要结构成分为函数，函数可以在程序中被定义完成独立的任务，独立地编译成代码，以实现 程序的模块化。 3、c语言运算符丰富，运算包含的范围很广； 4、c语言数据类型丰富。 5、c语言允许直接访问物理地址，即可直接对硬件进行操作，实现汇编语言的大部分功能； 6、c语言语法限制不太严格，程序设计自由度大，这样是c语言能够减少对程序员的束缚； 7、用c语言编程，生成的目标代码质量高，程序执行效率高，可移植性好； 4、合法标识符：AB12、leed_3、EF3_3、_762、PAS、XYZ43K2 file:/F|/khdaw/暑假/c语言习题/第1章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:17 不合法标识符：a*b2、8stu、D.K.Jon、if、ave#xy、#_DT5、C.D 5、F2:将当前编辑器中文件存盘 F10:调用主菜单 F4:程序运行到光标所在行 Ctrl+F9:当前编辑环境下，进行编译、连接且运行程序； Alt+F5:将窗口切换到DOS下，查看程序运行结果 6、 (1): * welcome you very good * (2): please input three number;5,7,8 max number is:8 7、main 8、User screen、Alt+F5 9、标识符必须是字母或下划线开头，大小写字母含义不同。由数字、字母和下划线组成； 关键字是一种语言中规定具有特定含义的标识符。关键字不能作为变量或函数名来使用，用户只能根据系 统的规定使用它们。 10、选择主菜单File项下拉子菜单中Save项或直接按F2键存盘。 file:/F|/khdaw/暑假/c语言习题/第2章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:12 1、符合C语法规定的常数为：0x1e、“abn“、1.e5 2、(1): 错误如下：int x,y=5,z=5,aver; x=7; aver = (x+y+x)/3; 结果如下：AVER=5 (2): 错误如下：char c1=a,c2=b,c3=c; printf(“a=%db=%c“end“n“,a,b); 结果如下：a=3b=A“end“ aabcc abc 3、 4、(1):9,11,9,10 (2):3,1,0,0 (3):11,19,31,1 5、(1):0 (2):0 (3):9.500000 (4):90 (5):10 (6):10 (7):65 (8):4 (9):4.500000 (10):1 (11):0 (12):20 (13):0 file:/F|/khdaw/暑假/c语言习题/第2章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:12 6、(5) 7、求x的绝对值 8、c(max=ab?a:b)?c:max; 9、B 10、D file:/F|/khdaw/暑假/c语言习题/第3章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 1、输入函数scanf的参数错误，应该为：scanf(“%f“, 2、|1234 1234 | 3、ff10 4、1,3,1 5、原字符串 左边加空格再加字符串本省，字符个数总和为5个 6、scanf(“%d,%d,%c,%c“, 7、printf(“a+b=%dn“,a+b); printf(“a-b=%dn“,a-b); printf(“a*b=%dn“,a*b); printf(“a/b=%dn“,a/b); printf(“(float)a/b=%fn“,(float)a/b); printf(“a%b=%dn“,a%b); 8、void main() float r; float s,c; printf(“please input the number:“); scanf(“%f“, if(r=0) s = 3.14*r*r; c = 2*3.14*r; printf(“s = %f, c = %fn“,s,c); else printf(“you input number is error!“); 9、void main() file:/F|/khdaw/暑假/c语言习题/第3章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 int n; printf(“please input the number:“); scanf(“%d“, if(n=100 file:/F|/khdaw/暑假/c语言习题/第3章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 Area = sqrt(s*(s-a)*(s-b)*(s-c); printf(“%fn“,Area); else printf(“you input the number is error!n“); file:/F|/khdaw/暑假/c语言习题/第4章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 1： 0 2： 20 3： (x20)|(x void main() char a,b,t1,t2; scanf(“%c,%c“, t1=ab?a:b; t2=a void main() int temp1=0,temp2=0,x,y,i=1; printf(“Please input (x,y): “); file:/F|/khdaw/暑假/c语言习题/第4章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 scanf(“%d,%d“, while(i*y) shang=%d,yushu=%d“,x,y,temp2,x-y*temp2); getch(); 9、 #include void main() float x,y,m=0,n=0; scanf(“%f,%f“, n=(x-2)*(x-2); m=(y-2)*(y-2); if(m+n) void main() int temp=0,month,year; file:/F|/khdaw/暑假/c语言习题/第4章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 printf(“Please input (year,month): “); scanf(“%d,%d“, if(year%400=0)|(year%4=0 if(month=2) if(temp)printf(“%d year %d month have 29 “,year,month); else printf(“%d year %d month have 28 “,year,month); else if(month%2=0) printf(“%d year %d month have 30 “,year,month); else printf(“%d year %d month have 31 “,year,month); getch(); 11、 switch(a/10) case 5:m=4;break; case 4:m=3;break; case 3:m=2;break; case 2:m=1;break; default:m=5; 12、 方法一： #include void main() int x,y; scanf(“%d“, if(x-5) y=x-1; file:/F|/khdaw/暑假/c语言习题/第4章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 else if(x=0) y=x; else if(x0 scanf(“%d“, if(x-5) if(x=0)y=x; else if(x0 scanf(“%d“, if(x-5) if(x=0)i=1; else if(x0 printf(“the %d years later complete!n“,count); 6、 void main() int i,temp=0,bit=0; for(i = 1 ; i int main(void) int steps = 29, i = 1; while ( steps % 7 ) steps = (30 * +i) - 1; printf(“Total steps: %dn“, steps); return 0; 8、 main() int i,j,k,n; printf(“the narcissus number is:n“); for(n=100;n=nleft long k = 1; float e = 1; n = 1; clrscr(); while ( fabs(1.0/k) = 0.000001) n+; e = e+ 1.0/k; k = k * n; printf(“%fn“,e); 15、 #include “math.h“ main() float x0,x1,x2,f0,f1,f2; x1=-10; f1=2*x1*x1*x1-4*x1*x1+3*x1; x2=10; f2=2*x2*x2*x2-4*x2*x2+3*x2; do x0=(x1+x2)/2; f0=2*x0*x0*x0-4*x0*x0+3*x0; file:/F|/khdaw/暑假/c语言习题/第5章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:17 if(f0*f1)1e-6); printf(“_2*x*x*x-4*x*x+3*x=0_n“); printf(“the root is %fn“,x0); file:/F|/khdaw/暑假/c语言习题/第6章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 1、 #include int divisor(int a,int b) int r; while(r=a%b)!=0) a=b; b=r; return b; int multiple(int a,int b) int d; d=divisor(a,b); return a*b/d; void main() int a,b,c,d; printf(“intput (a,b): “); scanf(“%d,%d“, c=divisor(a,b); d=multiple(a,b); printf(“ndivisor=%dttmultiple=%d“,c,d); 2、 #include void tongji(char a) int b3=0,0,0,i=0; while(ai!=0) if(ai=65)|(ai=97) file:/F|/khdaw/暑假/c语言习题/第6章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 b0+; else if(ai=48) b1+; else b2+; i+; printf(“zimu have: %d; shuzi have: %d; qita have: %d“,b0,b1,b2); getch(); void main() char a100; printf(“Please input a string: “); gets(a); tongji(a); 3、 #include int flower(int n) int x=0,i,j,k; i=(n%10); j= (n/10%10); k=(n/100); x=i*i*i+j*j*j+k*k*k; if(x=n) return 1; else return 0; void main() int i,n; file:/F|/khdaw/暑假/c语言习题/第6章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 printf(“Please intput n: “); scanf(“%d“, if(n999|n #define SWAP(a,b) t=b;b=a;a=t; main() float x,y,t; printf(“Enter two number (x,y): “); scanf(“%f,%f“, SWAP(x,y); printf(“nnExchanged:x=%f,y=%f“,x,y); getch(); 5、 #include int fib(int n) int p; if(n=0) p=0; else if(n=1) p=1; else p=fib(n-1)+fib(n-2); return p; void main() file:/F|/khdaw/暑假/c语言习题/第6章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 int n; printf(“Please input fib: “); scanf(“%d“, printf(“nnfibonacci=%d“,fib(n); 6、 #include long fac(int n) long f; if(n=0) f=1; else f=n*fac(n-1); return f; void main() int m,n; long f; printf(“Please input (m,n): “); scanf(“%ld,%ld“, f=fac(n+m)+fac(n); printf(“nnfibonacci=%ld“,f); 7、 #include void list() int i,j; for(i=1;i int he(int n) int i,s=0; for(i=1;i%d “,i,j); 9、 #include #define max 100 struct work long sid; char name15; workermax; int size=0; file:/F|/khdaw/暑假/c语言习题/第6章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 struct work *set_list() do printf(“nnPlease input (sid,name): “); scanf(“%ld,%s“, size+; while(workersize-1.sid!=0); return worker; void paixu(struct work a) int i,j,k;long t;char v15; for(i=0;iaj.sid)k=j; if(k!=i) t=ai.sid; ai.sid=aj.sid; aj.sid=t; strcpy(v,);strcpy(,);strcpy(,v); for(i=0;i float jiecheng(int n) long s=1;int i; for(i=1;i=0 ak=temp break k #define max 100 void main() float amax,s=0,average=0; int i,n; printf(“Please input N: “); /*输入要处理元素的个数*/ scanf(“%d“, printf(“nPlease input %d ge shu: “,n); /*输入90，85，92，77，80，62*/ for(i=0;iaverage) printf(“%.2f “,ai); /*输出90.00 ，85.00 ，92.00*/ 5、 /*题目：编写程序，输入一组整数，将他们排序后由小到大输出。*/ #include #define max 100 void main() int amax,j,i,k=0,t=0,n=0; printf(“Please input N: “); /*输入要处理元素的个数*/ scanf(“%d“, for(i=0;iaj) k=j; if(k!=i) /*元素排序前下标与排序后下标不符，则交换其值*/ t=ai; ai=ak; ak=t; file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 printf(“nn“); for(i=0;i #include void main() int d44=0,0,0,0,i,j; clrscr(); printf(“nPlease input 16 num: “); for(i=0;idji) /*左下角元素大于右上角元素则交换*/ dji=dij; for(i=0;i=i) printf(“t%d“,dij);/*为了使位数不同的数输出依然保持三角型*/ else file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 printf(“t“); 7、 *题目：输入一个3x4的二维数组，然后分别按行和按列输出。*/ #include #include void main() int d34=0,0,0,0,i,j; printf(“Please input 12 num: “); for(i=0;i #include void main() file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 char s150,s250; int i=0,j=0,t=0; printf(“Input one: “); gets(s1); while(s1i!=0) i+; /*统计s1中字符个数*/ printf(“nnInput second: “); gets(s2); while(s2j!=0) j+; /*统计s2中字符个数*/ for(t=0;t #include #define MAX 100 void main() char strMAX; int i=0,flage=0; int count=0; printf(“nPlease input a string: “); gets(str); while(stri) if(stri=a) flage=1; else if(stri=b) file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 if(flage=1) count+;flage=0; else flage=0; i+; printf(“the double char “ab“ count is %dn“,count); 10、 #include /*相对于第一种方法，这种方法能把同为最大的字符串全部打印出来。*/ #include int paixu(int a,int n) /*构造对长度为n的数组排序的函数*/ int i,j,t,k,temp; for(i=0;iaj) k=j; if(k!=i) t=ai; ai=ak; ak=t; temp=an-1; return temp; /*返回最大字符串的长度的值*/ file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 void main() char str150,str250,str350,str450,str550,str650; char str750,str850,str950,str1050; int count10=0,temp10=0,i,j; int paixu(int a,int n); for(i=1;i void main() int a100,b100,c100,i,m,n,j,k,temp=0,s; printf(“nm = “);scanf(“%d“, /*确定M的个数*/ file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 printf(“nn = “);scanf(“%d“, /*确定N的个数*/ printf(“nPlease input m ge shu: “); for(s=0;sbj) i-; k+; if(j=n) /*b处理到完*/ file:/F|/khdaw/暑假/c语言习题/第7章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:19 for(;) /*把b数组接到c后面*/ if(i=0) /*如果a处理完，结束。并做标记temp=1*/ ck=ai;temp=1;break; ck=ai; i-; k+; if(temp=1) break;/*标记temp=1，全部处理结束*/ for(s=0;s=*q; q+ (2) i void fun(char *str,char c) char *p; for(p=str;*p!=0;p+) if(*p!=c) *str+=*p; *str=0; void main() char str80,c; printf(“nPlease input a string: “); gets(str); printf(“nnPlease input delete char: “); scanf(“%c“, fun(str,c); puts(str); getch(); file:/F|/khdaw/暑假/c语言习题/第8章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 5、 /*从键盘输入单词，每个单词之间用空格隔开,“.”号结束输入，*/ /*将每个单词的第一个字母转化成大写字母。*/ #include #include char zhuanhua(char c) /*定义将小写字母转化为大写字母的函数*/ char C; if(c=a p1=data; printf(“nInput 8 number: “); for(i=0;i void main() int m,n,i; char a100,b100,*p,*q; file:/F|/khdaw/暑假/c语言习题/第8章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 printf(“Please input a string: “); gets(a); p=a;q=b; printf(“nnPlease input m and n(like 1,1): “); scanf(“%d,%d“, if( (strlen(a)=m) /*指针指向第一个要复制的字符*/ for(i=0;i void main() int a100,temp1=0,temp2=0,max=0,min=0,k; printf(“nPlease input 8 ge shu: “); for(k=0;kamax)max=k; /*用标记max最大值的下标*/ file:/F|/khdaw/暑假/c语言习题/第8章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:16 if(min=0) if(max=7) temp1=a0; a0=a7;a7=temp1; else temp2=a7;a7=amin; a0=amax;amax=temp2; else if(max=0) if(min!=7) temp2=a7; a7=amin;amin=temp2; else if(min=7) temp1=a0;a0=amax;amax=temp1; else if(max=7) temp2=a7;a7=amin; amin=a0;a0=temp2; else temp1=a0;temp2=a7; a0=amax;a7=amin; amin=temp2;amax=temp1; for(k=0;k #include int *paixu(int data,int n) int i,*p1,*p2,temp; p1=data; for(p1=data;p1=0) ai=ai*10+t; p+; if(*p)9|(*p) struct students char sid100; char name100; float score3; student; void main() int i; float j; printf(“nPlease input sid: “); scanf(“%s“,student.sid); printf(“nPlease input name: “); scanf(“%s“,); printf(“nPlease input 3 score:(like1,1,1) “);/*输入逗号隔开*/ scanf(“%f,%f,%f“, printf(“nsid = %s“,student.sid); printf(“nname = %s“,); j=(student.score0+student.score1+student.score2)/3.0; printf(“naverage = %.2f“,j); getch(); 3、 #include #include file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 #define F sizeof(student) #define NULL 0 typedef struct scores int english; int math; int c_language; int all; TP; typedef struct students char sid15; char name15; TP score; struct students *next; student; student *input() student *head,*p1,*p2; int n=0; char ch; clrscr(); head=(student *)malloc(F);head-next=NULL; do n+; printf(“nnPlease input %d student message: nn“,n); printf(“t%d student sid: “,n); p1=(student *)malloc(F);p1-next=NULL; scanf(“%s“,p1-sid); printf(“nt%d student name: “,n); scanf(“%s“,p1-name); printf(“nt%d student scores(englesh,math,c_language): “,n); scanf(“%d,%d,%d“, file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 p1-score.all=p1-score.english+p1-score.math+p1-score.c_language; if(n=1) head-next=p1;p2=p1; else p2-next=p1; p2=p1; printf(“nntttContinue or back (press y/n): “); ch=getch(); while(ch=y|ch=Y); return head; void average1(student *head) student *p; int j; clrscr(); p=head-next; while(p) j=p-score.all/3; printf(“nnname: %staverage: %d“,p-name,j); p=p-next; printf(“nnnPress eny key return.“); getch(); void average2(student *head) student *p;int n=0,temp1=0,temp2=0,temp3=0; p=head-next; while(p) file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 temp1+=p-score.english; temp2+=p-score.math; temp3+=p-score.c_language; p=p-next;n+; printf(“nnaverage english is : %dnaverage math is : %dnaverage c_language is : %dt“,temp1/n,temp2/n,temp3/n); student *sort(student *head) student *head1,*p,*q,*r; int temp1=0,temp2=0,temp3=0,temp4; char s15,n15; head1=head; for(p=head1-next;p-next!=NULL;p=p-next) r=p; for(q=p-next;q;q=q-next) if(q-score.allr-score.all) r=q; if(r!=p) strcpy(s,p-sid);strcpy(n,p-name); temp1=p-score.english; temp2=p-score.math; temp3=p-score.c_language; temp4=p-score.all; strcpy(p-sid,r-sid);strcpy(p-name,r-name); p-score.english=r-score.english; p-score.math=r-score.math; p-score.c_language=r-score.c_language; p-score.all=r-score.all; strcpy(r-sid,s);strcpy(r-name,n); r-score.english=temp1; file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 r-score.math=temp2; r-score.c_language=temp3; r-score.all=temp4; return head1; void output(student *head) student *head2,*p;int i=1; clrscr(); head2=sort(head); for(p=head2-next;p!=NULL;p=p-next) printf(“nnname: %stsid: %stenglish: %dtmath: %dtc_language: %dtaverage: %dtmingci: %d“,p-name,p-sid,p-score.english,p-score.math,p-score.c_language,p- score.all/3,i+); average2(head); printf(“nnnttPress eny key back.“); getch(); void main() student *head,*p1,*p2; int i=0,j=1; head=input(); do clrscr(); printf(“nn(1): average1.nn(2): average2.nn(3): sort.nn(4): output.nnn Please choose: “); scanf(“%d“, switch(i) file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 case 1: average1(head); break; case 2: clrscr();average2(head); printf(“nnnPress eny key retuen.“);getch(); break; case 3: clrscr();p1=sort(head); for(p2=p1-next;p2!=NULL;p2=p2-next) printf(“nttname: %stmingci:%d“,p2-name,j+);printf(“nnnPress eny key back.“);getch(); break; case 4: output(head); break; default: printf(“nYour choose is not right.“);break; while(i!=-1); 4、 #include #include #define NULL 0 #define F sizeof(worker) typedef struct work char sid15; char name15; int money; struct work *next; worker; int min=0,max=0; char a15,b15; worker *input() worker *head,*p,*q;int n=0; char ch; head=(worker *)malloc(F); head-next=0; do file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 n+; p=(worker *)malloc(F); p-next=0; printf(“nntPlease input %d worker message : “,n); printf(“n%d worker sid: “,n);scanf(“%s“,p-sid); printf(“n%d worker name: “,n);scanf(“%s“,p-name); printf(“n%d worker money: “,n);scanf(“%d“, if(n=1) head-next=p; q=p; max=p-money;strcpy(a,p-name); min=p-money;strcpy(b,p-name); else q-next=p; if(p-moneymax) max=p-money;strcpy(a,p-name); if(p-moneymoney;strcpy(b,p-name); q=p; printf(“ntty/n“);ch=getch(); while(ch=y|ch=Y); return head; void output() clrscr(); printf(“nThe max money is: %dttname is: %snn“,max,a); printf(“nThe min money is: %dttname is: %s“,min,b); void main() input(); file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 output(); getch(); 5、6、 #include“stdio.h“ #define F sizeof(stu) #define NULL 0 typedef struct student int sid; int average; struct student *next; stu;stu *head; stu *create() stu *p1,*p2; int n=0; char ch; head=(stu *)malloc(F);head-next=NULL; do n+; printf(“nnPlease input %d student message: nn“,n); printf(“t%d student sid: “,n); p1=(stu *)malloc(F);p1-next=NULL; scanf(“%d“, printf(“nt%d student average: “,n); scanf(“%d“, if(n=1) head-next=p1;p2=p1; else p2-next=p1; file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 p2=p1; printf(“nntttContinue or back (press y/n): “); ch=getch(); while(ch=y|ch=Y); return head; stu *select(stu *head,int x) stu *s; s=head-next; while(s) if(s-sid=x) break; s=s-next; return s; stu *insert(stu *head,int x,int y) stu *p,*r,*q; clrscr(); p=head-next; r=(stu *)malloc(sizeof(stu); r-sid=x; r-average=y; if(p=NULL)/*如果插入空表*/ file:/F|/khdaw/暑假/c语言习题/第9章 课后答案【khdaw_lxywyl】.txt2009-8-10 0:45:18 p=r; r-next=NULL; printf(“ninsert success!“); else while(xp-sid) /*找到插入的位置，按学号大小。（找到位置或者到了表尾都会跳出循环）*/ if(p-next=NULL)break; p=p-next; if(xsid) /*插到中间位置*/ r-sid=p-sid; r-average=p-average; p-sid=x; p-average=y; r-next=p-next; p-next=r; printf(“ninsert success!“); else if(x=p-sid) /*学号不能相同*/ printf(“nError-your input thi